Louwtjie Burger wrote: > Dumping a large file from memory using tar to LTO yields 44 MB/s ... I > suspect the CPU cannot push more since it's a single thread doing all the > work. > > Dumping oracle db files from filesystem yields ~ 25 MB/s. The interesting bit > (apart from it being a rather slow speed) is the fact that the speed > fluctuates from the disk area.. but stays constant to the tape. I see up to > 50-60 MB/s spikes over 5 seconds, while the tape continues to push it's > steady 25 MB/s. > > There has been NO tuning .. above is absolutely standard. > > Where should I investigate to increase throughput ...
Does your tape drive compress (most do)? If so, you may be seeing compressible vs. uncompressible data effects. _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
