Both machines are IBM xSeries 346 model 884042U with 6 drives in a RAID 5 array through an IBM battery backed controller. We had a couple of these lying around after replacing them with better, but they have been pretty stable workhorses for us. I'm checking on whether the RAM is ECC -- the techs available at the moment aren't sure. The current machines are "transitional", and it may not be too late to set the permanent servers up with ECC memory. Is it something I should fight for? For specs on the base machines, before we dressed them up: http://www-132.ibm.com/webapp/wcs/stores/servlet/ProductDisplay?productId=8741193&langId=-1 -Kevin >>> Scott Marlowe <smarlowe@xxxxxxxxxxxxxxxxx> >>> On Mon, 2005-11-14 at 17:20, Kevin Grittner wrote: > running on dual hyperthreaded Xeons, with data on RAID5. > ERROR: could not read block 649847 of relation 1663/16385/16483: > Invalid argument If you were running on top of a RAID 1+0 or RAID 5 array, such an error would likely never have happened, since it would have been detected by the controller, and either the bad block would be mapped out or the drive would be kicked out of the array and you'd get a system alert telling you you had a bad drive in your array. Are you running on quality hardware (ECC memory, Server class SCSI drives, battery backed cache hardware RAID array, etc...) or just whatever was laying about unused. ---------------------------(end of broadcast)--------------------------- TIP 4: Have you searched our list archives? http://archives.postgresql.org