Hi, we're experiencing some troubling performance issues with our nfs clients. One of the symptoms is degraded performance of directory walks with hot caches and expired attribute caches: "find -ls" in the kernel tree goes from about 4s (cold caches) to 1.5s (hot vm caches) and then to 18s after actimeo. Network traffic increases by about the same amount. "echo 3 > /proc/sys/vm/drop_caches" brings back the initial performance (~4s), but so do writing 1 or 2. This was reported almost two years ago in https://bugs.debian.org/702477 but I don't know if this is a known issue upstream. Seen on various kernel versions, up to 3.18. Is there anything we can do to track this down, or are there known workarounds for this? Thanks, Julien -- Julien Cristau <julien.cristau@xxxxxxxxxx> Logilab http://www.logilab.fr/ Informatique scientifique & gestion de connaissances -- 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
