Hi Daniel, Daniel Pocock wrote: > > > Hi, > > I'm testing a problem with the following combination: > - SB700/SB800 type controller in AHCI mode (in a HP Microserver N36L) > - Seagate Barracuda 1TB 7k2 drive with NCQ Is that a disk with 4k hardware sectors (Advanced Format)? Where does you partition start? At sector 63 or 2048? ;-) > > I've got a fresh 256MB partition, formatted ext4, mounted > barrier=1,data=ordered, write-cache enabled (hdparm -W 1 /dev/sdb) and > shared over NFS. > > When the NFS client writes, > - unpacking a source tarball, many small files, iostat reports speeds > under 500kBytes/sec > - dd conv=fsync, iostat reports about 50MB/sec > > If I set up a USB disk on the same box, with a partition formatted > exactly the same way, the iostat reports the write speed (unpacking the > same tarball) is over 5MBytes/sec - not so fast, but 10 times faster > than the AHCI device. So USB is at speed 10 times less, right? Martin -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
