Re: Writing performance problem with SAS1068

2007-02-07 Thread Bernardo Innocenti
Douglas Gilbert wrote: > You may like to check that Write Cache Enable is on with: > 'sdparm --get=WCE /dev/sdd'. Yeah, yeah! Works fine once I toggled the WCE to 1. Writing flies at 70MB/s, which is extremely good for those desktop-grade disks (Seagate Barracuda SATA 250GB @7200RPM). Thank yo

Re: Writing performance problem with SAS1068

2007-02-06 Thread Douglas Gilbert
Bernardo Innocenti wrote: > Hello, > > I've stumbled onto a strange performance problem on a new server: > reading from disks is fast (70-80MB/s), but writing is extremely > slow (13-15MB/s). I've measured it like this: > > dd if=/dev/zero of=/dev/sdd bs=4096 count=65536 conv=fdatasync > 65536+0

Writing performance problem with SAS1068

2007-02-06 Thread Bernardo Innocenti
Hello, I've stumbled onto a strange performance problem on a new server: reading from disks is fast (70-80MB/s), but writing is extremely slow (13-15MB/s). I've measured it like this: dd if=/dev/zero of=/dev/sdd bs=4096 count=65536 conv=fdatasync 65536+0 records in 65536+0 records out 268435456