StableBit DrivePool Release Final

StableBit DrivePool

StableBit DrivePool is now available as a Release Final.

Download it here:

Full change log:

Updated user manual:


For those who have participated in the community translation effort, thank you for doing that. This version has some significant community edits to the Japanese and Italian translations since the last RC, among other corrections.

If you’d like to participate in the community translation effort, head on over to (powered by OneSky) and submit your corrections, or simply vote on some of the existing ones. Your edits will be included in the next release.

Compared to version, this version now includes 3 new languages:

  • Dutch
  • Japanese
  • Russian

Bug Fixes

Aside from the new features, a very big part of this release was about fixing any existing bugs and ensuring the stability of the application. In fact, if you look at the full change log, almost every change prefixed with [Issue #…] is a fix that resulted from a user having a conversion with technical support that ended up spawning a Code Change Request. Most code change requests eventually ended up in a fix made to the code.

For the more complex code changes, sometimes additional information was made publicly available on our issue tracking system, for example see: Issue #27704

After a lot of hard work, today, we are down to 0 open bugs for StableBit DrivePool. As a result this version is being made available as a Release Final.

But we’re not done, if you do encounter an issue that you’d like to report, you can do so here:

I’d like to give a big thank you to Christopher Courtney for heading up the technical support effort and for handling the myriad of issues that have come up over the testing cycle of this release.

In this post, I want to highlight the most significant new features or changes since the last release final of StableBit DrivePool, which was version Because I’ve already talked about some of the new features available in this release in previous blog posts, I won’t be going into much detail on those topics again.

Let’s dive right into a short summary of each new feature that I would like to highlight.

User Feedback

User Feedback

One very visible new feature is the new user feedback system.

StableBit DrivePool is built as a task-oriented application. That means that almost every long running action is treated like a task that can end in various levels of success or failure. With user feedback, this is now exposed in the user interface.

User Feedback Colors

The result of each finished task is color coded using the above levels of severity.

Additionally, a failed task may have actions that you can perform on it in order to resolve the failure.

See user manual: UI Overview > Feedback

Drive Removal Overhaul

Files in Use

The process of removing a drive from the pool was mostly overhauled for this release in order to make it more robust and less intrusive.

In summary:

  • The pool no longer becomes read-only while a drive is being removed.
  • Duplicated open files can remain open on a drive that’s being removed.
  • Unduplicated open files can be force closed (safely) on a drive that’s being removed.

For more information see my previous blog post (under Drive Removal Improvements):

See user manual: Removing a Drive from the Pool

Hierarchical Pooling

HybridPool Hierarchy

Hierarchical pooling support is a major new feature of this release, and I’ve covered it extensively in a previous blog post.

In summary:

  • A pool can now be added to an existing pool, just like a regular drive.
  • Each pool in the hierarchy has separate file duplication, file placement and balancing settings.
  • A child pool can set individual file duplication, file placement and balancing settings on files that are stored in a parent pool.

For more information see my previous blog post (under Hierarchical Pooling):

See user manual: Adding a Drive to the Pool > Hierarchical Pooling

Read Striping Priorities

Each pool member (drive or pool) now has a read striping priority associated with it, and StableBit DrivePool will always try to read from the highest priority class available for each duplicated file.

For example, if a file exists both locally and in the cloud, that file will always be read from the local drive or pool. Similarly, if a file exists on an internal drive as well as on an external USB drive, it will always be read from the internal drive.

See user manual: Performance Options > Read Striping

Disk Tooltip Updates

Disk Tooltip

Disk tooltips have been updated as well with more information about each pool member.

A Cloud Pool

The type of the pool member will also be shown like this.

See user manual: Disks List > Tooltips

Performance UI Updates

Pool Performance

In addition to showing the instantaneous read and write speeds on the pool, StableBit DrivePool will now show how many files are currently open on the pool. Hovering over the open file count will bring up the file open rate tooltip (i.e. file opens per second).

If your pool is consuming CPU cycles, and you’re not sure why, this is an important performance metric to take into account.

See user manual: Performance UI > Pool Performance

File System Performance Improvements

This version of StableBit DrivePool features some significant low-level performance improvements to the pooling file system. It should boot faster and require less overhead when opening files on the pool.

Mount Speed Improvements

In order to speed up pool mount time and avoid missing disk warnings, each pool is now aware of how many pool parts it is comprised of.

At boot time, a pool will wait for new disks to arrive for up to 10 seconds, but only if any pool parts are missing. Otherwise, the pool is mounted instantly.

Many Thousands of Open Files

Previous versions of StableBit DrivePool would struggle to maintain a good file open rate when dealing with many thousands of concurrently open files. This would cause CPU bottlenecks, especially when dealing with large pools and Windows Search.

Thanks to an updated algorithm, version can now handle up to 1 million concurrently open files without suffering a performance penalty in its pooling file system (provided that you have enough RAM).

DPCMD Updates

DPCMD is the command line utility that comes with StableBit DrivePool and offers some additional functionality.

In this version, DPCMD can now list all of the open files on the pool.


Additionally, you can now force close one or more open files like this:

>dpcmd force-close-open-files P:\ *.MP4

Unlike other methods of force closing handles, this will safely close only pool part handles by communicating with the pooling file system directly. It will leave the pool handle open, but any I/O attempted on the pool with that handle will fail form that point on.

Miscellaneous Updates

Here are some other miscellaneous but noteworthy updates:

  • Real-time file size tracking was reworked.
  • Reparse points were reworked:
    • Proper support for remote to local symbolic links.
    • Support for non-Microsoft reparse points.
  • Advanced settings are now stored in the JSON format at: %PROGRAMDATA%\StableBit DrivePool\Service\Settings.json

For a complete list of all of the changes, see the full change log.

StableBit CloudDrive

StableBit CloudDrive

The Release Final of StableBit CloudDrive is now available as well.

Download it here:

Full change log:

This release features mostly bug fixes and is meant to be used together with StableBit DrivePool