Hi Ralf, Ralf Gross wrote: > I'm testing our new changer which is equipped with 2 LTO-4 drives. > What should I expect from LTO's hw compression? I've seen LTO-3 tapes with > 800+ GB data. Here are the volbytes number I got with LTO-4 so far. > > volbytes: > 1,164,080,268,288 > 1,138,440,038,400 > 1,180,908,417,024
I am very interested in this too. So far I have got even less than that on a volume, though I know that the data I am currently testing with is not *that* compressible. Tomorrow I intend to do some benchmarking of different block sizes to see what effect they have on performance and compression. > I'm just wondering if I have to set a special density code with mt > (which I don't know at the moment)? LTO-3's code was 0x44 if I > remember correctly, but I *think* the default shoulb be ok. I couldn't > find any density code for LTO-4 with google. My drive is using 0x46: [EMAIL PROTECTED]:~# mt -f /dev/st0 status SCSI 2 tape drive: File number=51, block number=0, partition=0. Tape block size 0 bytes. Density code 0x46 (no translation). Soft error count since last status=0 General status bits on (81010000): EOF ONLINE IM_REP_EN Is that what yours is using too? I'm using mt-st by the way, it seems more featureful than GNU mt, which was the one that was already installed on my Ubuntu box. ------------------------------------------------------------------------- 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
