Test: HighPoint RocketRaid 3120 PCIex1 2xSATA controller under FreeBSD 7.1-PRERELEASE

[fluffles.net]

Dieter wrote:
>> If you get about the same scores with dd, try using a higher read-ahead
>> (vfs.read_max value, set it to 32 for example). Also sometimes it's
>> required to use a higher blocksize to get full potential, try:
>>
>> newfs -U -b 32768 /dev/<raid device>
>>
>> Warning: using 64KiB blocksize you risk hanging the system under heavy
>> load (like 2 bonnies running simultaniously).
>>     
>
> What's this about 64KiB blocksize hanging the system?
> Hang awhile then recover, or hang forever need a reboot?
> Is this a RAID thing or are normal disks at risk?
>   

See this, posted 2 years ago to freebsd-fs:
http://freebsd.monkey.org/freebsd-fs/200610/msg00024.html

Scott Long says the bug in vfs_bio.c is known but difficult to fix. They
also argued that using a 64KiB blocksize should not be necessary. I have
been getting slightly higher scores with 64KiB blocksize though, also
with perfect alignment.

32KiB should be safe to use, i have not managed to crash the system
under heavy I/O load.

I'm curious if my suggestions gave you any better results, though.

Regards,
Veronica