On T, 2005-05-31 at 17:08 +1200, Mark Kirkwood wrote: > Luke Lonergan wrote: > > Tom, > > > > This is a story that is evolving. Anyone else use StorageReview? Great > > comprehensive drive benchmarks: > > http://www.storagereview.com/ > > > > Check the comparisons between 15K RPM SCSI drives and the 2004 Western > > Digital 10K RPM SATA (Raptor) drives. The Raptors are an interesting hybrid > > of SCSI-related tech and desktop tech, and were some of the first drives > > with SCSI-like command queuing TCQ/NCQ. > > > > I think the last remaining issue in moving to SATA for all enterprise use is > > the lack of decent SATA controllers, though 3Ware (http://www.3ware.com) is > > getting there: > > http://www.3ware.com/link/pdf/Serial-ATA.pdf > > http://www.3ware.com/products/benchmarks_sata.asp > > > > Although the benchmark numbers are pretty good, they have only published > (what looks like) results for sequential IO. It would be interesting to > see the random ones, as this would tell us how effective the TCQ > implementation is. > RAID10
The following are from iozone results for 3Ware with 8 x WD 74G Raptors on 1.6GHz Opteron and 2GB RAM RAID10 "Throughput report Y-axis is type of test X-axis is number of processes" "Record size = 8 Kbytes " "Output is in ops/sec" " Initial write " 1352.90 " Rewrite " 413.31 " Read " 369.01 " Re-read " 368.07 " Reverse Read " 355.94 " Stride read " 358.01 " Random read " 358.29 " Mixed workload " 360.55 " Random write " 359.80 RAID5 "Throughput report Y-axis is type of test X-axis is number of processes" "Record size = 8 Kbytes " "Output is in ops/sec" " Initial write " 1178.55 " Rewrite " 145.91 " Read " 369.06 " Re-read " 364.37 " Reverse Read " 357.83 " Stride read " 357.79 " Random read " 358.04 " Mixed workload " 359.70 " Random write " 360.62 Seems to have either very low overhead for RAID5 or something else is keeping RAID10 speed down. -- Hannu Krosing <[EMAIL PROTECTED]> ---------------------------(end of broadcast)--------------------------- TIP 1: subscribe and unsubscribe commands go to [EMAIL PROTECTED]