[OpenAFS] bonnie++ on OpenAFS

Achim Gsell achim.gsell@psi.ch
Mon, 22 Nov 2010 18:00:41 +0100


bonnie++ on OpenAFS with sizes above 8192 behaves strange on my Linux =
systems: after writing up to 5-7 files with 1GB each, write performance =
drops from 50-60 MB/s to around 3MB/s. At the same time OpenAFS client =
and server start playing ping pong on the network. The load on the =
network is constantly above 50 MB/s when the problem occurs, going down =
to ~35 MB/s after some time - while the "real" transfer is still around =
3 MB/s. After killing bonnie++ everything is OK again.=20

Tested with 2 clients:
Scientific Linux 5, kernel 2.6.18-194.17.1.el5 and 2.6.18-194.17.4.el5=20=


$ cmdebug localhost 7001 -cache
Chunk files:   4096
Stat caches:   6144
Data caches:   4096
Volume caches: 200
Chunk size:    262144
Cache size:    1048576 kB
Set time:      no
Cache type:    memory

Scientific Linux 5, kernel 2.6.18-194.17.4.el5

Server and clients are test-systems without any other load.

Any ideas?