KernelTrap: Low Latency and Filesystems

“Continuing the earlier discussion about low latency and Ingo
Molnar’s voluntary kernel preemption patch, the conversation moved
onto the affect a filesystem can have on latency. Specifically, 2.6
maintainer Andrew Morton noted that ReiserFS was known to have some
latency issues in both the 2.4 and 2.6 Linux kernels, ‘resierfs:
yes, it’s a problem. I ‘fixed’ it multiple times in 2.4, but the
fixes ended up breaking the fs in subtle ways and I eventually gave
up.’ However, he did go on to note, ‘actually, the 2.4 low-latency
patch does still have some reiserfs fixes, so it’s probably better
than reiserfs in 2.6.’

“When asked if ext3 was a better choice for low latency work,
Andrew Morton replied, ‘ext3 is certainly better than [reiserfs],
but still has a couple of potential problem spots. ext2 is probably
the best at this time…'”

Complete
Story