[ltp] Thinkpad T43 cached read Speed(hdparm -T) mystery
Henrique de Moraes Holschuh
Wed, 25 Jun 2008 14:01:52 -0300
On Wed, 25 Jun 2008, email@example.com wrote:
> When it was running a Ubuntu hoary a few months ago(too lazy to
> update), with vanilla 2.6.18 kernel, hdparm -T shows about 1800MB/sec.
> However, now I'm in hardy, with ubuntu 2.6.24-18 kernel, the hdparm -T
Might be the ZEROPAGE removal stuff that went in in 2.6.24-18. Try 22.214.171.124
just released, it is supposed to fix a performance regression in the
If the regression in hdparm -T speed is indeed related to ZEROPAGE, that
means hdparm -T is a completely meaningless test.
> 2.What exactly does hdparm -T measure(processor bus speed?)?
Probably nothing useful.
> Is it a good gauge for performance? If it is not a good guage for
> performance, what is?
Your real workload is the only gauge for performance that matters.
"One disk to rule them all, One disk to find them. One disk to bring
them all and in the darkness grind them. In the Land of Redmond
where the shadows lie." -- The Silicon Valley Tarot