Red Hat Bugzilla – Bug 508338
Improving performance relating to random i/o on ext3 filesystems
Last modified: 2013-02-25 14:05:56 EST
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The issue is slow access times for our 99% random block levelIO. Each read requires reading in multiple inodes before the data block when inodes are not cached. We can't seem to keep inodes in cache even with the vfs_cache_pressure=0 setting.
These poor IO response times are noticeable in our application. We ran the exact same test with the same SAN and a server with a different OS and filesystem and saw good IO response times.
I guess that's something for kernel guys, not for basic system directory layout package. Reassigning.
Got a testcase for this or a more complete description? Is this multiple random reads within a single file, or (sounds more likely) randomly reading files scattered around a filesystem?
No response to the question after 3.5 years, I guess it's not terribly critical.
Feel free to re-open w/ more info if needed.