Author Archives: maru

Two new btier releases have become available. btier-1.3.10 is hopefully a final bug fix release. It should be stable and ends btier-1.3.x series development. Btier-1.3 will still be maintained should bug fixes be necessary. All the new development will take … Continue reading →

btier-1.3.9 solves a number of bugs, including one early free() that would cause random read failures. Ouch! This release has been extensively tested on 32bit and 64bit systems. Btier-1.3.9 will become the next stable production version, assuming that no bugs … Continue reading →

Introduction Btier is an automated tiering block device for the Linux kernel. It works with any type of file-system and it’s purpose is to automatically move data between different block devices in such a way that the performance is improved … Continue reading →

Introduction: It has been a while since I updated this blog about btier development. At a slow but steady pace I am however still fixing bugs and adding features. This article will explain what has changed as well as what … Continue reading →

This version of btier seems to be very stable indeed. One of the problems that has now been solved was that btier could deadlock on high vfs cache pressure. Mostly when btier was not used with writethrough enabled on a … Continue reading →

For some time people have been using btier in production. Some even use complex configurations that stack drbd and Oracle on top of btier. The good news is that even heavy users have not reported problems with btier. Therefore the … Continue reading →

This release solves a bug that can lead to loss of data when btier is used with SSD’s and a recent kernel that supports discard / trim. Upgrading is highly recommended.

This release dramatically improves random read performance. This has been achieved by introducing a thread pool and implementing aio for random reads. The performance of the 0.9.9.9 release was: seq_read : io=12288MB, bw=501371KB/s, iops=125342 , runt= 25097msec rnd_read : io=2985.3MB, … Continue reading →

What’s in a name TIER has been renamed to BTIER to improve the relevance of results returned by search engines. BTIER current status The btier code is now at 0.9.9.2 and I hope to release a stable 1.0 version within … Continue reading →

Introduction This version of TIER comes with a significant number of changes. The meta data has changed to support resizing of the TIER device. Therefore this version of TIER is not compatible with previous releases. New features This version of … Continue reading →