Quoting sf...@users.sourceforge.net: > dan...@zoltak.com: >> Due to the AUFS being the RootFS and the raw NFS mounts are mounted on >> the RootFS could this in fact be causing AUFS to do unnecessary lookups? > > I don't think so. > Because the root dir is always cached and its cache will never be > discarded. Every access (to anywhere) may cause the revalidation of the > root dir, but I don't think it is so slow. It will be longer to > revalidate files (every componets in the path) on the raw NFS than > revalidating the root dir since the root dir is only one.
Is there anyway to validate this? > How much RAM does your system have? 16GB and 8 cores. Something that I have noticed. On the AUFS system if I do: # ps -ef |grep flush root 2893 2 0 Jan24 ? 00:00:00 [kdmflush] root 2902 2 0 Jan24 ? 00:00:00 [kdmflush] root 4639 2 0 Jan24 ? 00:00:04 [flush-253:0] lsof -p 4639 COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME flush-253 4639 root cwd DIR 0,17 260 2 / flush-253 4639 root rtd DIR 0,17 260 2 / flush-253 4639 root txt unknown /proc/4639/exe On the non-AUFS system if I do the same: # ps -ef |grep [f]lush root 319 2 0 Jan25 ? 00:00:00 [pdflush] root 320 2 0 Jan25 ? 00:00:00 [pdflush] root 2042 2 0 Jan25 ? 00:00:00 [kdmflush] root 2052 2 0 Jan25 ? 00:00:00 [kdmflush] I'm not sure if this has any relevance? There is no doubt something odd is happening. The performance difference has to lie with the AUFS kernel module somewhere? Any other theories? ------------------------------------------------------------------------------ Special Offer-- Download ArcSight Logger for FREE (a $49 USD value)! Finally, a world-class log management solution at an even better price-free! Download using promo code Free_Logger_4_Dev2Dev. Offer expires February 28th, so secure your free ArcSight Logger TODAY! http://p.sf.net/sfu/arcsight-sfd2d
