Michael Galloway schrieb: > i'm going to just add this bit of data into the mix. dd onto and > off the tape device: > > # dd if=/dev/zero of=/dev/nst0 bs=65536 count=100000 > 100000+0 records in > 100000+0 records out > 6553600000 bytes (6.6 GB) copied, 61.687 seconds, 106 MB/s > # mt -f /dev/nst0 rewind > # dd of=/dev/null if=/dev/nst0 bs=65536 count=100000 > 100000+0 records in > 100000+0 records out > 6553600000 bytes (6.6 GB) copied, 58.3182 seconds, 112 MB/s > # mt -f /dev/nst0 rewind > # dd if=/dev/zero of=/dev/nst0 bs=65536 count=300000 > 300000+0 records in > 300000+0 records out > 19660800000 bytes (20 GB) copied, 181.502 seconds, 108 MB/s > # mt -f /dev/nst0 rewind > # dd of=/dev/null if=/dev/nst0 bs=65536 count=300000 > 300000+0 records in > 300000+0 records out > 19660800000 bytes (20 GB) copied, 215.185 seconds, 91.4 MB/s
I also get these numbers with my LTO-4 drives and dd or HP's test tool hptapeperf. hptapeperf writes directyl from memory to tape (like dd), no disks involved. You can also choose between 2:1 or 3:1 compression ratio. I thought I should get higher write speed with a compression ratio of 3:1 or 2:1, but I can't get beyond ~110 MB/s. The drive is capable of 120 MB/s native and up to 240 MB/s with compression. BTW: I had no problems with the btape test and a LSI SCSI HBA (no FC). Ralf ------------------------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Still grepping through log files to find problems? Stop. Now Search log events and configuration files using AJAX and a browser. Download your FREE copy of Splunk now >> http://get.splunk.com/ _______________________________________________ Bacula-users mailing list Bacula-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bacula-users
