Messages in this thread | | | Subject | Re: Linux SCSI benchmarking tool?? | From | Valdis.Kletnieks@vt ... | Date | Tue, 19 Aug 2003 01:03:38 -0400 |
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On Mon, 18 Aug 2003 21:52:54 PDT, "Nayak, Samdeep" <Samdeep_Nayak@adaptec.com> said:
> have used dd, dt, IOmeter and rawio utilities so far and each seemed to > represent a different picture to me on the same setup (Single target with > few LUNS). (DD showed good performance on an ext2 mounted file system till > I realized that I was writing to the buffer and not writing on the raw > drive). Since I am trying to catch up with the SCSI world, I am just > wondering if any one else has tried any other utilities that would provide > better results or am I doing something wrong here??
Those tools report different things because they are measuring different aspects of the performance. For many system configurations, the fact that 'dd' is writing on a buffer rather than a drive is actually a *feature*, as you might care about just how much of a boost the cache is giving you - I don't care how fast my compile writes to disk, I care how fast the cache and page subsystems actually present the data to userspace...
"better results" depends on the question - otherwise "42" is as good an answer as any, for exactly the reasons that Deep Thought gave.... ;) [unhandled content-type:application/pgp-signature] | |