Le Sat, 18 Oct 2014 17:26:40 +0800 vous écriviez: > Hi, > I am using xfs on a raid 5 (~100TB) and put log on external ssd > device, the mount information is: > /dev/sdc on /data/fhgfs/fhgfs_storage type xfs > (rw,relatime,attr2,delaylog,logdev=/dev/sdb1,sunit=512,swidth=15872,noquota). > when doing only reading / only writing , the speed is very > fast(~1.5G), but when do both the speed is very slow (100M), and high > r_await(160) and w_await(200000). What are your kernel version, mount options and xfs_info output ? > 1. how can I reduce average request time? > 2. can I use ssd as write/read cache for xfs? Sure, using bcache and other similar tools. -- ------------------------------------------------------------------------ Emmanuel Florac | Direction technique | Intellique | <eflorac@xxxxxxxxxxxxxx> | +33 1 78 94 84 02 ------------------------------------------------------------------------ _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs