On Thu, May 4, 2017 at 7:52 AM, Wols Lists
On 03/05/17 19:42, Lew Wolfgang wrote:
IIRC we tested with EXT4 once and found XFS to be just a bit faster. But that was years ago and memory is fading.
Not sure whether it was LWN or the linux-raid list ...
There's a new variant of ext4 in the works, called "lazy-ext". And it's specifically aimed at improving raid performance.
Basically, the problem is that even when streaming large data files, there's a fair bit of metadata updating going on in the background. And this triggers a lot of small, random writes. Guaranteed to make a raid controller have heartburn. So there's some tweak they're testing that consolidates all these small writes into one big stream to improve performance. I can't remember the figures, but they do look good.
I'm not familiar with the ext4 work, but that sounds similar to what xfs did about 5 years ago. xfs now accumulates more metadata changes in ram before writing them to the journal. They leverage that additional buffer space to perform the equivalent of merges and elevator sorts. It had a significant impact on cutting down on the overhead associated with xfs file system overhead. Greg -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org