I think I figured out why I am now only able write a maximum 512K block size now. Its hardware compression being enabled. When I did my earlier tests, I had it turned off.
On 1/7/2010 10:01 AM, Brian Debelius wrote: > I am just trying to understand things, so please bear with me. I > understand that the recommended block size is 256K. > > I thought that earlier this week, I tested the LTO-3 drive with a 1M > block size. But attempting to do so again, does not work. So now it > looks like the actual maximum block size for the drive is > 512M(524288). So now my questions. > > #dd if=/dev/zero of=/dev/nst1 bs=524288 count=1 > This completes successfully. > > If I set the Maximum Block Size = 524288 in the sd, and run btape test, > This fails. Why? > > If I set the Maximum Block Size = 523264 (1024 less) in the sd, and > run btape test, > This succeeds. Why? > > If I round this block size to a 4096 division, it would be 520192. > If I set the Maximum Block Size = 520192 in the sd, and run btape test, > This succeeds, but it says it is using a 520092 block size Why? > > > ------------------------------------------------------------------------------ This SF.Net email is sponsored by the Verizon Developer Community Take advantage of Verizon's best-in-class app development support A streamlined, 14 day to market process makes app distribution fast and easy Join now and get one step closer to millions of Verizon customers http://p.sf.net/sfu/verizon-dev2dev _______________________________________________ Bacula-users mailing list Bacula-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bacula-users
