On 23 April 2014 22:44, Malahal Naineni <malahal@xxxxxxxxxx> wrote: > Cedric Blancher [cedric.blancher@xxxxxxxxx] wrote: >> On 23 April 2014 22:24, Malahal Naineni <malahal@xxxxxxxxxx> wrote: >> > Cedric Blancher [cedric.blancher@xxxxxxxxx] wrote: >> >> Are there any options to improve the Linux NFSv4 performance over a >> >> high latency connection? >> >> >> >> We currently use Solaris/Illumos as NFSv4 server and client over a >> >> cross continental Internet connection. Latency is terrible (~220ms) >> >> but the counter this by running work in parallel so the latency is >> >> mostly mitigated. >> >> >> >> We now wish to migrate (short: Away from Oracle because support is >> >> basically unbearable) to Linux (tested SuSE 13.1 and current Fedora) >> >> and build times are 17 times (!!!) SLOWER than on Solaris/Illumos. >> >> >> >> Are there any tunables besides actimeo=300? >> > >> > rsize and wsize may help! You need to figure out if the read is the >> > issue or the write before you dig further. >> >> I already tried to tune rsize/wsize, making them both smaller or the >> maximum of 1048576 bytes, with no effect. >> >> One possible theory is that maybe something in Linux doesn't allow >> multiple requests to be issued in parallel and waits for each request >> to be completed before issuing the next one? > > Linux NFS client can issue I/Os in parallel. Should be limited by number > of RPC slots though. What controls the number of RPC slots? is there a tunable? Is there something to monitor the usage? Ced -- Cedric Blancher <cedric.blancher@xxxxxxxxx> Institute Pasteur -- 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
