1

May 04, 2018

The Ultra Copier

This is a big change, which was long due. The central piece of code that shuffles data from a file to its backup copy was completely redone. The previous version is still perfectly fine, but it is now several years old and we've learned a thing a two during that time.

In short, the ultra copier is:

⦁    Faster in bulk copying and faster in processing of smaller files.

      Details are here - https://bvckup2.com/wip/19042018

⦁    Faster in delta copying. Much faster. To the point that it can now
      shovel data between two NVMe drives with virtually no impact on
      the speed over regular bulk copy.

      Details are here - https://bvckup2.com/wip/25042018

⦁    Copying is now resumable after cancellations and IO errors. In fact,
      you can now yank an USB drive from its port in the middle of a write
      and Bvckup 2 will automatically correct the file corruption that this
      may cause, while preserving as much of existing data as possible.

      Details are here - https://bvckup2.com/wip/30042018

      *  Not that yanking a drive is ever a good idea though.

Additionally, the ultra copier looks at the exact drive type (HDD, SDD, NVMe, etc.), USB connection details and a network protocol version to adapt its IO profile for the setup.

If you have some time, do read through the linked posts. It's one of more interesting changes to the program in a while.

2

May 04, 2018

Support for retrying on transient failures

Starting with this release the backup engine will retry backup steps when they fail in a certain way. By default, the retrying is enabled for network-related failures as this is the number ones source of intermittent failures that tend to resolve themselves in a short amount of time.

The retry schedule is 20 times 15 seconds apart, configurable as per usual.

The engine already had a list of so-called "fatal errors" which cause a backup run to be aborted when encountered. This list includes errors like "Device not found", "Volume dirty" and everyone's all time favorite "Disk corrupted".

Details are here - https://bvckup2.com/wip/23042018

3

May 04, 2018

Disabling tray alerts for missed backups

By a popular request, it's now possible to disable systray icon blinking when a periodic backup misses its scheduled run. The error will still be logged, but the icon won't blink.

Details are here - https://bvckup2.com/wip/03052018

* However, this is a bit like sweeping dust under the carpet. A better
option is to suppress or to delay these alerts exactly in more precise
manner - https://bvckup2.com/support/forum/topic/1053

4

May 04, 2018

Notable fixes

⦁    Resolved an issue with losing UI config file on machine reboots

UI's ini file *was* saved in response to Windows "we are rebooting" notification, but it was initiated _after_ the UI responded to the latter. So in some cases Windows ended up nuking the program before the save was completed.


⦁    Resolved two issues with handling of file symlinks

1.  The engine erroneously skipped symlinks that were pointing back into the source tree. This is a _folder_ processing logic (because we'd end up in a loop if we were to allow that). File symlinks we should be following regardless of where they point.

2. When copying a file via symlink, the engine used wrong API to query its size, so it ended up always thinking the size was 0. This would've not been a problem if the engine didn't have an optimized copying routine for zero-sized file. This routine works by creating a backup file and then closing it write away, without attempting an IO.

⦁    Resolved an issue with "Another instance is running" popup

This was due to the program being started twice in rapid succession.

5

May 04, 2018

Smaller changes

⦁    Flushing is now Off by default for removable devices

Previously the engine would force-flush file buffers after copying each file if the backup device was removable. In retrospect this is not really needed, because it's a duplicate of Windows' per-device write cache policy, which is what needs to be changed IF a device is indeed prone to sudden removals.

⦁    Delta copying thresholds are now 16 MB and 64 MB (see below)

That is, when enabled, delta copying is now used for all files over 64 MB and for recently-modified files over 16 MB, whereby "recently" is "within last 30 days".

6

May 04, 2018

⦁    New progress bar for bulk and delta copying

Any excuse to redesign a progress bar is a good excuse. Here's the 5 years of evolution of the damn thing - https://bvckup2.com/wip/18042018

⦁    Ctrl-A now selects all text in edit boxes

As it turns out it's NOT a default behavior of native Windows controls.

⦁    "More" links are now shown in blue

In some configuration windows there's a plaintext "More" at the bottom right corner. It used to be dark gray, so some people assumed it was a disabled option and never bothered to try it... even though it changed color invitingly on hover.

As of this release, these are blue. Looks a bit more busy, but hopefully a bit more actionable too.

7

May 04, 2018

⦁    Better handling of the OneDrive folder and offline files

1. The UI now doesn't complain when you are setting up a backup of C:\ that goes into a OneDrive folder:

        C:\    =>    C:\Users\foo\OneDrive

Previously, it would say "Destination is a subfolder of the source" and refuse to OK the setup.

2. The engine now understands "offline files" and complains intelligently when it fails to copy them - https://bvckup2.com/wip/24042018

⦁    Pre/post-commands now launch .bat files via "cmd /c ..."

If a pre/post-command ends with ".bat" and the whole command is a filename, then the engine will launch it with "cmd /c <command>".

⦁    Templating of new backup jobs is now simpler

This is an internal change that cleans up the initialization of the default exclusion list. Just rest assured that it's all tidy and neat there now.

8

May 04, 2018

Misc

Direct update link - https://bvckup2.com/update
Thread for any issues - https://bvckup2.com/support/forum/topic/1061

9

May 07, 2018

Releases 79.0.1  -  79.0.3

These went out over the course of past few days to patch an issue each.

In particular,
79.0.1 patched an issue with finalizing partial copies
79.0.2 - an incorrect self-consistency check in the ultra copier code,
79.0.3 - an issue with running (or rather *not* running) on XP

The last of these will show up through in-app updates shortly, but you can also update to it manually via https://bvckup2.com/update

10

May 08, 2018

Release 79.0.4

⦁    Resolved an issue with retrying on network errors while _scanning_
⦁    Resolved an issue with "error 0" being shown for failed file deletes

11

May 15, 2018

Release 79.1

⦁    Resolved an issue with copying files that are _shrinking_
⦁    Added support for AppExecLink reparse points

12

May 20, 2018

Release 79.2

⦁    Resolved an issue with resuming delta copying after a write failure
      due to an out-of-disk-space condition
⦁    Resolved an issue with resuming delta copying after a cancellation
      that was preceded by a write failure
⦁    Resolved an issue with sending alerts over TLS
      As per - https://bvckup2.com/support/forum/topic/1069

13

May 25, 2018

Release 79.3

⦁    Resolved an issue with scanning getting stuck in case of network
      errors under certain circumstances.

⦁    Resolved an issue with delta copying - the copying module would
      erroneously deem a delta state invalid if the only change on the
      previous run was to the last block of the file *and* the file length
      was not a multiple of 64KB.

      As per - https://bvckup2.com/support/forum/topic/1070

⦁    Added an option for explicitly selecting a VSS provider to use for
      shadow copying.

14

May 29, 2018

Release 79.4

⦁    Resolved an issue with shadow copying not working on XP
⦁    Resolved an issue with archiving trimming reporting too many
      completed steps in a presence of network errors
⦁    Added a safeguard to catch sporadic crashes in the guts of Lavasoft
      Adaware when issuing SetFileCompletionNotificationModes requests

15

Jun 26, 2018

Release 79.5

⦁    Resolved an exotic issue with ultra copier in a presence of network
      errors - in some edge cases when a network connection drops some
      of file system requests still may complete successfully, while most
      won't. The ultra copier assumed that all will fail and that led to some
      misplaced panicking on its part.

⦁    Fixed scheduler's behavior when an over-the-network real-time job
      ran into a non-network related error. It's a mouthful, but basically it
      means that when a share, for example, ran out of space, the engine
      kept running the job in a loop, because it assumed it was a retryable
      error.

⦁    Revised how the installation fingerprint is calculated. As in, Microsoft
      is at it again, breaking things with recent W10 updates.

⦁    Added support for "final" qualifier to default exclude/include rules.
      This is something that can't be explained briefly. Stand by for a link
      to a separate detailed post...

⦁    Added a manual override to support (much) older Samba versions
      that don't return correctly truncated timestamps unless a file is
      closed and re-opened.

16

Aug 03, 2018

Release 79.6

⦁    Added native support for dynamically modifying source/backup
      paths using current date and time variables.

      The gist of it is here - https://bvckup2.com/wip/02082018
      Full spec is here - https://bvckup2.com/support/forum/topic/1091

⦁    Reworked "Run on low priority" option to also allow reducing
      *disk* load in addition to just lowering program's process priority.

      See here for details - https://bvckup2.com/wip/01082018

⦁    Reworked the retrieval of file IDs during the planning phase (these
      are used to track moved and renamed files) - the process is now fully
      parallelized, with IDs being retrieved by a pool of threads. In short,
      this step now should be noticeably faster... unless you are running
      on a single-core CPU, in which case you should see no difference.

⦁    Patched up archiving code to strip leading space when archiving
      files with no name but just an extension. Previously, if we were
      archving ".abc" it ended up being saved as " (2018-08-01 ...).abc".
      That is with a space in front of the opening brace. No more now.

⦁    Fixed an issue with copying Alternate Data Streams in out-of-space
      conditions.

⦁    Fixed an issue with delta copying when updating a file that has
      shrunk since the last time and running into an error trimming
      the backup copy (e.g. because of the network error).

⦁    Assorted cosmetic fixes to the backup logs, mostly to make them
      read more concisely in collapsed form.

Release 79.6.1 - 79.6.4

⦁    Fixed several issues with the program complaining that "Something
      went wrong" under certain conditions.

      All issues were related to the logging module, or more specifically
      to an incorrect self-consistency checks that were added in 79.6 as
      a part of the logging module cleanup.

     That is, these weren't the bugs in the actual code. These were the
     bugs in statements that verified correctness of the code, in real-time.
     So they caused the program erroneously panic over an otherwise
     perfectly valid code.

17

Sep 05, 2018

Release 79.7

⦁   Added an option for NOT copying *folder* timestamps. This is the
     last phase of a backup run, that is logged under "Updating folder
     information" section.

     This is a manual override for now, but we may later give it some UI
     presence or even promote to a default. See this post for details -
     https://bvckup2.com/support/forum/topic/1104

⦁   Fixed two issues with the ultra copier. One was related to updating a
     backup copy of a actively shrinking file and another - to handling of a
     backup location going away precisely after all the copying was done,
     but the backup file wasn't yet closed.

⦁   Fixed an issue with copying NTFS alternate streams on Windows XP.
     It is basically unsupported, but the program tried to do it anyway
     and panicked when it saw no required API support.

⦁   Fixed an issue with editboxes no longer vertically centering the input
     text on preview builds of Windows 10. In some cases the input was
     so off center that it was clipped.

     This was caused by Microsoft outright breaking the handling of
     EM_SETRECT message in "Edit" controls. Completely destroying
     it for no apparent reason or explanation.
    
⦁   Fixed an issue with the Task Scheduler task that Bvckup 2 creates
     to launch itself at user's logon, when set to run as Administrator.

     As of this release the task is called "Bvckup 2, for %SID%", whereby
     the last bit is the user account's SID. Previously, the name ended
     with "... for user@domain" and that caused some issues if the user
     account or the computer itself was renamed.

⦁   Fixed an at-launch issue when the engine cannot open a log file for
     a backup job. In certain cases the program would panic and exit.
     Now it doesn't.

⦁   Reworked the on-launch check of whether the program's window is
     visible on any monitor.

     There is a built-in Windows function for that, but apparently it will
     sometimes fail (and show that the window is completely off screen)
     *unless* the program first enumerates all present monitors. This is
     most likely a quirk with a 3rd party display driver... though in the
     only reported case it was NVIDIA.

18

Sep 17, 2018

Release 79.8

⦁   Fixed an XP/WS2003 issue with handling copying aborted due to a
     certain errors.
    
     The issue was due to the need to emulate newer API for IOCP (IO
     completion ports) on these Windows versions and the emulation
     code was incorrectly handling the case of a device abruptly going
     away.

⦁   Patched "Backup everything" option from the systray menu to
     queue jobs in the order they appear in the UI. As per this report -
     https://bvckup2.com/support/forum/topic/1108

19

Sep 19, 2018

Release 79.9

⦁   Resolved an issue with destination scanning, which manifested in
     logging entries being recorded at the wrong log level. Internally,
     the issue was due to not marking destination scanning phase as
     such, so the engine ended up re-using source scanning rules for
     the destination scan. In the vast majority of cases this made no
     difference, but in some cases it did, potentially causing more files
     to be retained in the backup than required.

     The issue was introduced in 79.8 release, so an update is strongly
     recommended if you are running 79.8.

20

Sep 26, 2018

Release 79.10

⦁   Changed "archive_modified" override to NOT require deleting option
     to be set to "archive" as well. That is, it's now possible to set a backup
     job to archive just modified files and not deleted ones.

⦁   Resolved an issue with file system information not being saved for
     newly created jobs. This caused this information to be re-queried on
     every run, which in turn caused a real-time job to run back-to-back
     even when there were no real changes.

⦁   Reverted default window size to its original values. An earlier change
     was to let Windows size it, but in some cases it resulted in a window
     being set too wide and tall.

21

Oct 02, 2018

Release 79.11

⦁   Resolved an issue with file system information querying/caching.

     This is related to the issue resolved in 79.10. Both were caused by an
     internal rework of the backup prep phase done in 79.9.

22

Oct 21, 2018

Release 79.12

⦁   Fixed an issue with querying destination file system and device
     information.

     In some cases the program would try and do it before backup folder
     is created, logging one or two errors as a result of that. Operationally
     this made little difference in the vast majority of cases, but it was still
     a bug, so fixed.

⦁   Fixed an issue with erroneous "Login required" failures after a
     successful authenticated connection to a publicly inaccessible share.

     That is, if you were backing up to/from a share that _required_ an
     authentication and that wasn't accessible otherwise, then on the
     first backup run the program would successfully connect to the
     share (using credentials supplied), but then it would bail out
     erroneously thinking that it still didn't have a connection.

⦁   Fixed an issue with redrawing pushpin icons in the Backup To/From
     fields in the Backup Settings dialog when collapsing "More section"
     of the window. In some cases there would be some junk drawn in
     place of the icons, because the latter weren't re-drawn after the
     window was transformed.

⦁   Fixed an issue with copying progress bar variable precision %-age
     display.

     It's a mouthful for this - when copying larger files, the UI will show
     the progress bar and the %-age done so far. Depending on the
     copying speed and size of file, the percentage may show one or
     more decimal places (up to 3) to make sure there _is_ some non-
     trivial activity shown even for slow-going copies. The issue was that
     this bit was broken in recent releases and the UI always showed no
     decimals.

⦁   Added retrying on "VSS is busy" condition when creating a source
     volume snapshot.

     The context is this - Shadow Copying service may refuse creating a
     volume snapshot if another snapshot is being created at the very
     same moment. This is an inherently retryable situation, so this
     release adds just that - the engine will now retry up to 10 times 30
     seconds apart when running into this condition.

     Retry parameters are configurable through the INI.

     Retrying is enabled only when "More Options" > "Shadow Copying"
     is set to "Require", and not for the "As needed" setting.

⦁   Speeded up saving of destination snapshots at the end of a backup.

⦁   Suppressed logging of deduplicated files during the scanning phase.

     These were logged because dedup'd files are reparse points and RPs
     were unconditionally logged before this change.

⦁   Suppressed complaints about deprecated INI entries when upgrading
     from pre-78 releases.

23

Oct 30, 2018

Release 79.13

⦁   Added support for pre-computing delta state of existing backups
     https://bvckup2.com/wip/30102018
     https://bvckup2.com/support/forum/topic/1131

⦁   Added support for displaying absolute next-run times in the UI
     https://bvckup2.com/wip/29102018

⦁   Changed the layout of About window a bit.

⦁   "Switch mode" menu option is now shown by default on Windows
     Server installations.

⦁   "Backup everything" option from the tray menu now does NOT apply
     to disabled jobs.

⦁   Fixed tabbing order in the Backup Settings window.

⦁   Fixed Ctrl-A support in edit boxes.

24

Nov 07, 2018

Release 79.14

⦁   Fixed cosmetic issue with fading transitions in the UI, i.e. reworked
     code to eliminate occasional flicker during fade-ins and fade-outs.

⦁   Fixed an issue with the UI not showing changes in backup state.

     The issue surfaced when running without Administrator privileges.
     About 20 minutes after launching the program the UI would stop
     receiving updates from the engine, so while you could start a job
     with Go and it would execute, the UI wouldn't actually show any job
     progress.

     Another symptom was that when an activation code was used to
     license an installation, the UI would confirm the activation going
     through, but then keep on saying that the program was still in trial
     mode. That too was due to the UI not receiving respective updates
     from the engine.    

     #   Kudos to Andy, Lanka, Michael and John for helping with
           reporting and tracking down this issue.

     For those on their coffee break, here's some light reading as to Why
     this was happening.

The post-mortem

The cause of the issue was a trivial mistake in the code that tried reading some VSS-related information without first checking that VSS was available. This led to an "Access denied" fault, which should, under normal circumstances, trigger a crash. So it should've been a really visible issue that would've been caught in testing on the first pass.

However in this case the code in question was in a callback set with SetTimer() function. When the top-level UI code called DispatchMessage(), the control went to user32.dll, which issued the callback, the callback ran that code and the code crashed.

You'd think what difference does it make, a crash is  a crash... Yes, exactly. Welcome to the club.

Apparently, callbacks issued by SetTimer() are framed by a pair of RtlActivateActivationContextUnsafeFast() and RtlDeactivateActivationContextUnsafeFast() calls, which set up and tear down their own SEH handler. So the timer callback code can crash all it wants and you'll be none the wiser.

Here's a sample code -
https://gist.github.com/apankrat/ce6d15e5a6aac681257257ad5809ca9b

So what happened in Bvckup's case is that it would receive a timer callback, which will run its internal event loop. The loop will dispatch event handlers and one of them will throw a SEH exception, which will be promptly eaten by user32.dll instead of being passed up to  the UI for reporting.

This left the UI thinking that its event loop was still active, so on the next timer callback the UI would see that the loop is still busy and it would skip running it - hence completely stalling the event  processing, including the reception of the updates from the engine.

Long story short - set your exception handlers for all your callbacks from Windows API or end up seeing your code behave in a way that makes no sense whatsoever.

25

Dec 12, 2018

Release 79.15

⦁   Added an option for quickly reloading a backup job via the right-
     click menu. This is an advanced option so it requires holding Ctrl
     down when opening a menu - https://bvckup2.com/wip/12122018

     This option is meant specifically for re-reading job settings after
     applying a manual override. Previously this required a program
     restart. Now it doesn't, so - a progress.

     It is also now possible to reload a job using external command-l
     line control, which compliments nicely already present "load"
     and "unload" commands.

⦁   Added human-friendly description for ERROR_FILE_CORRUPT and
     ERROR_DISK_CORRUPT errors. The program will also log an advice
     to check disk for mark-up and hardware errors as soon as possible.

⦁   Added an option for automatically re-activating a license when the
     installation fingerprint changes. Details are available on as-needed
     basis.

⦁   Changed scan thread count to be an option tied to the source and
     destination instead of being specified for local/remote location types.

⦁   Changed the run counter used for the %RUN#...% variable to *not*
     include backup runs that produced no changes.

     As per - https://bvckup2.com/support/forum/topic/1135
     See https://bvckup2.com/support/forum/topic/1091 for the context.

⦁   Changed "Create Backup" flow to allow destination folder to be a
     subfolder of the source, with a warning. Previously this was only
     allowed if destination was the OneDrive folder, and it was flat out
     disallowed in earlier releases.

⦁   Fixed an issue with delayed display of the copying progress.
     As per - https://bvckup2.com/support/forum/topic/1132

     The root cause was that the service and UI processes have their own
     microsecond-resolution clocks that are used for high-prevision things
     such as IO timers and some such. These clocks are started when the
     process starts, so in service mode they end up being offset relative to
     each other (because the UI typically starts some time after the service).

     So what happened is that the start time of current backup step was
     recorded by the engine using this clock rather than the system clock.
     It then passed it to the UI for display, but on UI's scale it was offset
     and appeared in the future => hence the delay.

⦁   Fixed an issue handling out-of-disk-space condition when saving
     destination snapshot at the end of a backup run.

26

Dec 21, 2018

Release 79.16

⦁   Resolved an issue with bvckup2.exe starting to eat ~10% of CPU once
     machine's uptime goes over 49 days.

     This was a good one.

     For internal housekeeping tasks the engine uses a millisecond
     resolution clock that is stored as 64 bits. This is plenty enough
     for storing milliseconds, but there was one place in the code that
     treated it as 32-bit.

     The problem was with the code that scheduled timers. You tell it
     that in X ms you want a callback, and it gives you a callback around
     that time. Timers.

     This code sorts all scheduled timers into logarithmicaly-spaced
     buckets similar to "timer wheels" as used in the Linux kernel [2].

     The problem was with a bit of code that determined how far out the
     next timer was from _now_. It erroneously treated milliseconds as
     a 32-bit value, so after (2^32/1000/60/60/24) days of uptime this
     code invariably decided that the next time was already past due.

     This caused the main loop in the engine to spin without sleeping
     and that led to elevated idle CPU usage.

     BUT. You are rightfully thinking - how come this only affects 79.15?

     Excellent question. Prior to this release RDTSC value was offset so
     that it would read 0 at the moment of _program_ launch. This meant
     that the 10% CPU issue was still there, but it didn't manifest itself
     until the _program_ was up for 50 days. This is not a common case,
     so the whole issue remained unnoticed since... well... pretty much
     version 0.1.

     Then, in 79.15 this RDTSC offset was removed to sync internal clocks
     between the engine and the UI. This resolved the first "Fixed" entry
     on 79.15 change log, but it also pushed the CPU issue into the
     spotlight as there *is* a fair number of boxes with good uptime.

     All in all though, it's all compiler's fault. Entirely.
    
     [1]  https://en.wikipedia.org/wiki/Time_Stamp_Counter
     [2]  https://lkml.org/lkml/2005/10/19/46

⦁   Resolved an issue with backup jobs auto-disabling themselves. In
     particular this happened when the program was running in service
     mode *and* if the UI was not launched within first 30 minutes from
     the service launch.

     Again, this was specific to 79.15 because it included a rework of the
     UI-to-engine communication protocol. One part of the change had to
     do with verifying program's self-consistency and one of the checks
     failed if the UI wasn't present. This led to the program entering a
     "safe mode" of sorts when it disabled a backup job after a run as a
     precaution.

⦁   It's now possible to use $QUOTE in job's description to have it
     expanded into job's custom queue name if there's one set. This is
     related to https://bvckup2.com/support/forum/topic/934

     The same change also adds BVCKUP_queue env. var to the pre/post
     commands and email alert templates.

27

Dec 29, 2018

Release 79.17

⦁   Resolved an issue with post-backup delay for real-time jobs not being
     observed consistently.  That would be the setting behind "Edit details"
     next to "Backup Settings" > "When to backup" > "In real-time" option.

29

Jan 23, 2019

Release 79.19

⦁   Added "etc_name" and "etc_path" variables to the pre/post-backup
     script env variable set. Etc_name is set to the name of job's settings
     folder (e.g. backup-0003) and etc_path is set to the folder's full path.

⦁   Added stricter validation of responses for storage device queries as
     some of these may come from 3rd party drivers and be not exactly
     up to Microsoft's specs.

⦁   Tidied up the log produced by the storage tracking module.

⦁   Resolved an issue with the engine not "seeing" removable drives that
     are first safely ejected and then plugged back in.

⦁   Resolved an issue with "Copy line" and "Copy block" options being
     mixed up in the log viewer's context menu.

30

Feb 04, 2019

Release 79.20

⦁   Reworked monitoring of mapped network drives.

     First, drives that appear offline after program's start, but can be
     "resuscitated" with Windows' help are now correctly recognized as
     online after connection is re-established. This bit got broken in
     79.18 with introduction of the new storage tracking module.

     Kudos to Greg for reporting the issue and helping with isolating it.

     Second, the engine now also detects network drives going offline,
     which is something it didn't do before at all.

⦁   Reworked reporting of ini/override warnings.

     In particular, this relates to reporting bad override entries on job's
     reload. As of this release, the engine tracks which configuration
     setting was picked up from which INI file and it will report this file
     when logging an INI warning.

     Kudos to Martin for running into this -
     https://bvckup2.com/support/forum/topic/971/6386

⦁   Added workaround for buggy SD card readers.

     SD card readers of certain vendor will for reasons unknown sometimes
     report that "the volume is not ready" when the volume is in fact A-OK.
     In other times they would refuse to report drive's geometry or partition
     information. The program can now tolerate this eccentric behavior.

⦁   Added workaround for strange 'sparse reparse' points.

     This is second workaround for an issue with bizarre reparse points
     surfacing in C:\Windows folder, always somehow attached to Sparse
     files. See https://bvckup2.com/support/forum/topic/1116 for details.

     The workaround itself is to treat a reparse point as a regular file IF
     its reparse tag is less than 0x00100000 (hex) and if it has a Sparse
     attribute set. This can be disable in job's settings if needed.

⦁   Cosmetic changes to the logs - tidied up messages here and there,
     removed extraneous line breaks, etc.

31

Feb 19, 2019

Release 79.21

⦁   Assorted UI tweaks and changes, including faster double-buffered
     custom control painting, revised and unified color palette (for reds,
     blues and grays), patched up tabbing order is several dialogs and
     fixed hints in "Add new filter" window.

⦁   Resolved an issue with handling of a swap file when running out of
     disk space during the copying phase of backup.

⦁   Resolved an issue with logging of missed-a-run email alert failures.

Revisions

⦁   79.21.1 fixes a small color issue with the Welcome Guide.
⦁   79.21.2 fixes an issue with progress bars not showing progress  
     during  scanning and planning phases.

Keep in mind that the latest revision won't show up via in-app checks for updates if the installation already runs a 79.21 release. Instead it can be downloaded from https://bvckup2.com/update for a manual update.

32

Mar 04, 2019

Release 79.22

⦁   Added check to detect dead symlinks during the scan as per -
     https://bvckup2.com/support/forum/topic/1162

⦁   Added an alternative warning for when creating a new backup job that
     points at existing non-empty destination folder AND when "Deleting"
     option is changed to "Keep backup copies":
     https://bvckup2.com/support/data/destination-exists-warning-alt.png

     Same warning, with "Deleting" left at its default "Archive" setting:
     https://bvckup2.com/support/data/destination-exists-warning.png

⦁   Resolved an issue with internal delta state clean up. This is referring to
     the removal of block-hash state files after respective source file is either
     deleted or shrunk down to no longer qualify for delta copying.

⦁   Resolved an issue with updating empty files when a System attribute is
     set on their backup copy.

     Previously this would fail with "Access denied" error due to a certain
     (rather obscure) provision in the file system API. With this release
     Bvckup2 will clear this attribute off the backup copy prior to updating
     it. This is an extension to an existing mechanism that clears ReadOnly
     and Hidden attributes, so the program now basically checks if any of
     these three attributes are set on the backup copy and clears them if
     they are.

⦁   Further UI improvements to double-buffered control rendering.

33

Apr 03, 2019

Release 79.23

⦁   Reworked the program mode switching process.

     Read all about it here - https://bvckup2.com/wip/29032019

⦁   Reworked storage monitoring to be asynchronous. The initial scan of
     the storage stack is still done synchronously (that is, the program
     waits for it to complete before continuing with its initialization), but
     all subsequent updates in response to device/volume activity is now
     done asynchronously, in the background.

     The main reason for the change is that despite all the efforts to avoid
     making any blocking or slow requests, there are still cases when even
     the most trivial request may take several seconds to complete. This
     includes cases of not fully spun up HDDs, dying drives that are still
     unsure if they want to die completely or not, etc.

⦁   Added support for requerying faulty storage volumes. This is related
     to the previous change. Apparently there exist device/drive combos
     that announce arrivals of new storage volumes before these volumes
     are actually operational. So if the program attempts to query basic
     volume details _immediately_ after its alleged arrival, there are cases
     when this request will fail.

     Previously, a volume like this was assumed to be faulty and ignored.
     So any jobs bound to this volume remained in "Waiting for device"
     state and didn't get to run.

     With this change, the program will try and re-query the volume once,
     in 5 seconds after the original attempt. If this too fails, only then the
     volume will be marked as broken and ignored.

⦁   Added support for verifying file size after copying. With this release
     the copying module will check if the resulting size of a backup copy
     as reported by the file system matches up with the expectation.

     This is added for one very specific case - for FAT volumes (not FAT32
     or ExFAT, just plain FAT) that accessed remotely, through Samba.
     Apparently in this case it's possible to create a file larger than 4 GB
     in size, with all writes completing successfully, but the resulting file
     size will be 0. This is some issue with Samba/FAT combination, so
     this check is basically meant to detect this combo and warn about it.

⦁   Resolved an issue with the storage monitoring module. The size of
     the storage stack information was growing by 20 bytes per device,
     per rescan due to cross-references between devices and volumes
     not being cleared correctly.

     This is obviously not a big problem unless there's a lot rescanning
     going on... which is exactly what happened in one reported case,
     where a dying flash drive was repeatedly generating "physical
     layout changed" events. This caused the stack information size
     swell in size, eventually growing over the maximum size of the
     UI-to-engine protocol message... which triggered an internal sanity
     check in the code and shut down the program.

     In good news, that sanity check worked as designed.

⦁   Resolved an issue with scanning errors of the top folder - that is, if
     the program ran into a _retryable_ error when just starting to scan
     either the source or destination folder, the retrying didn't work as
     expected. Fixed now.

⦁   Resolved an issue with the About window - in some cases it would
     show an "action" button, i.e. "Reactivate", partly off the screen and
     have a problem with showing the right license status.

Revisions

⦁   79.23.1 automatically expands "How to send" window if advanced
     options are configured.
⦁   79.23.2 fixes an issue with not being able to open Backup Settings
     window if DACL or SACL copying is enabled *and* email alerts are
     enabled. This was due to an invalid self-consistency check for the
     state of the window when it was put into respective state.

Keep in mind that the latest revision won't show up via in-app checks for updates if the installation already runs a 79.23 release. Instead it can be downloaded from https://bvckup2.com/update for a manual update.

34

Apr 10, 2019

Release 79.24

⦁   Enabled collection of the device health data.

     The storage monitoring module now queries SMART/NVMe health
     data from local storage device, if possible.

     When the program starts up, it first does a quick device scan just to
     collate basic device information. This scan is done synchronously -
     the backup engine waits for it to be completed before entering
     the "running" state.

     Then, once started, the engine then polls devices for their SMART
     data and this is done asynchronously, in the background, because
     retrieving this data can be slow and it may also require spinning up
     the drives (in theory it shouldn't, in practice - sometimes it does).

     After that it will also query SMART data from new devices that get
     plugged into the machine. This too is done asynchronously.

     SMART data is not (yet) refreshed periodically, so this version does
     not _monitor_ SMART status per se. Nor does it actually report it
     through the UI. Health status of the devices is logged in the storage
     log and the summary of it is also logged in the central program log.

     The main goal behind this change is to complete gradual roll-out of
     the new storage module and evaluate it against larger installation
     base:

     79.18 introduced the new storage monitoring module, sans SMART.
     79.23 switched the module to use asynchronous scanning.
     79.24 enabled the gathering of the SMART data.

      If all goes well (it should), the next step will be the tracking of SMART
      data over time and integration into the UI as a first-class feature.
      
⦁   Reworked the handling of faulty storage volumes - this has to do with
     how the engine deals with volumes that can't be queried for their
     basic information.

     79.23 introduced a single re-query attempt under certain conditions,
     but these conditions proved to be incorrect and sometimes caused
     the volumes to be re-queried perpetually, in 5 second intervals.

⦁   Cleaned up storage module logging - it's just marginally better
     looking and a bit more pleasant to read... if that's your thing.

⦁   Resolved an issue with the storage module - in certain cases the
     volume extent information (offset/size) were recorded incorrectly,
     which caused the tracking ID of respective device to become ill-
     formed, throwing off device tracking. This should be fixed now.

⦁   Resolved an issue with UI transitions - in certain cases the UI would
     erroneously trip an internal self-consistency check when validating
     the layout of a window after it was transformed from one state to
     another. This affected More options" page of Backup Settings,
     "Device Tracking" and "How To Send" dialogs.