> I have had extremely bad performance historically with onboard SATA chipsets
> on Linux. The one exception has been with the Intel based chipsets (not the
> CPU, the I/O chipset).
This board has Intel chipset. I cannot remember the exact type but it
was not in the low end category.
<Intel ICH7 SATA300 controller>
kernel: ad4: 152626MB <SAMSUNG HD160JJ ZM100-33> at ata2-master SATA150
kernel: ad4: 152627MB <SAMSUNG HD160JJ ZM100-33> at ata3-master SATA150
> It is very likely that you are having problems with the driver for the
> Are you running RAID1 in hardware? If so, turn it off and see what the
> performance is. The onboard hardware RAID is worse than useless, it
> actually slows the I/O down.
I'm using software raid, namely gmirror:
GEOM_MIRROR: Device gm0 created (id=2574033628).
GEOM_MIRROR: Device gm0: provider ad4 detected.
GEOM_MIRROR: Device gm0: provider ad6 detected.
GEOM_MIRROR: Device gm0: provider ad4 activated.
GEOM_MIRROR: Device gm0: provider ad6 activated.
Geom name: gm0
1. Name: mirror/gm0
Mediasize: 160040803328 (149G)
1. Name: ad4
Mediasize: 160040803840 (149G)
2. Name: ad6
Mediasize: 160041885696 (149G)
I tried to do:
vfs.read_max: 6 -> 32
but I could not reach better disk read performance.
Thank you for your suggestions. Looks like I need to buy SCSI disks.
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