> > Can we please revert fix it or revert > > 556b27abf73833923d5cd4be80006292e1b31662 before release. > > That commit ID doesn't make any sense, and doesn't seem to have > anything to do with any statistics counters that your email talks > about. So regardless, you'd need to explain why that commit causes the > problems you talk about, I'm not going to revert a random commit that > doesn't even look what you describe. Sorry correct problematic commit is commit 77f4135f2a219a2127be6cc1208c42e6175b11dd Author: Vivek Haldar <haldar@xxxxxxxxxx> Date: Sun May 22 21:24:16 2011 -0400 ext4: count hits/misses of extent cache and expose in sysfs The problem is that every IO operation in ext4 bangs on this super block cache line when it checks the extent cache and then updates the hit/miss count. On a system with more than two sockets this is very costly in terms of interconnect traffic under high IO load. A straight revert has a minor conflict on a trace statement that was added later. -Andi Original patch: commit 77f4135f2a219a2127be6cc1208c42e6175b11dd Author: Vivek Haldar <haldar@xxxxxxxxxx> Date: Sun May 22 21:24:16 2011 -0400 ext4: count hits/misses of extent cache and expose in sysfs The number of hits and misses for each filesystem is exposed in /sys/fs/ext4/<dev>/extent_cache_{hits, misses}. Tested: fsstress, manual checks. Signed-off-by: Vivek Haldar <haldar@xxxxxxxxxx> Signed-off-by: "Theodore Ts'o" <tytso@xxxxxxx> -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html