FreeBSD 8.0 Performance (at Phoronix)
mav at FreeBSD.org
Tue Dec 1 15:22:05 UTC 2009
Alexander Motin wrote:
> Threaded I/O activity could get much benefit from NCQ-aware disk driver.
> It is not included in default FreeBSD kernel, but it would be nice to
To check possible NCQ effect, I've built test setup with new 320GB
7200RPM Seagate drive connected to Intel ICH10R controller. I've run
IMHO more reasonable benchmark/raidtest tool from ports on whole device,
to execute pregenerated random mix of 10000 random-sized (512B - 128KB)
read/write requests using default ata(4) driver and new ahci(4):
Number of READ requests: 5029.
Number of WRITE requests: 4971.
Number of bytes to transmit: 655986688.
Number of processes: 32.
ata(4) - no NCQ:
Bytes per second: 12455402
Requests per second: 189
ahci(4) - with NCQ:
Bytes per second: 19889778
Requests per second: 303
Results are repeatable up to the 4-th digit. Average time per request is
5.29ms and 3.3ms respectively, that seems realistic for this drive.
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