On 04/13/2011 01:34 PM, Cal Webster wrote: > >> tar -zxf with a large file on this machine takes 1.5 minutes, but takes >> only 10 seconds on any of its siblings. CPU usage seems high while >> untarring, with lots of user and sys cycles being used, but almost no >> wait cycles. It doesn't matter whether I untar on a local disk, or on a >> fiber channel SAN volume, it's slow anyway. 1) Are you untarring from *and* to the SAN volume or is the source on the local volume? 2) What kind of local drives? If the local drive is IDE or SATA it is possible the machine is using PIO mode. That would match the symptoms of very high CPU usage and very slow I/O (yes - I've seen it happen with SATA drives with certain Supermicro chipsets). -- Benjamin Franz