On Mon, Nov 18, 2013 at 12:37:31PM -0500, J. Bruce Fields wrote: > One problem he's seeing was RHEL5-specific, the other is the known ext4 > problem that's been discussed before. Ok, didn't know there was a RHEL bug. > (Basically, ext4 has a tradeoff between correctness, lookup performance, > and compatibility with some buggy old clients: > > 1. turn off dir_index and performance on large directories may > suffer, but it's correct and any client will be happy. > 2. turn on dir_index and return 32-bit cookies: now you get > directory loops on large directories due to random hash > collisions. > 3. turn on dir_index and return 64-bit cookies: some clients seem > to then return errors to 32-bit applications doing readdirs. > Cookies have been 64-bit since NFSv3 and 32-bit Linux clients > deal with this fine (it fakes up its own small integer offsets > to return to applications), but apparently some other clients > return errors on readdir. > > So currently we default to 3 and if people complain, tell them to turn > off dir_index and complain to their client vendor....) Or people could use a filesystem taking care of that. In addition to taking care of the directory index XFS also has other advantages like much better support to get the metadata operations to disk a lot more efficiently. ... working hard on my marketing skills.. -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
