How big is your backup? If it fit completely in the spool area the behavour seem lead to the fact tha your bottleneck is the tape throughput. Backup rust faster to the spool area, but the tape writing take the same time. I believe that spooling only gain performance when the FD cannot feed enough data to keep the tape streaming (typically during an incremental/differential backup), otherwise direct writing is faster. Too bad the disk-to-tape operation of spooling is done suspending the backup-to-disk operation (no concurrency with double buffering) and this limits the usefulness of spooling (as far as I know).
-------------------------------------------------------------------------- Ferdinando Pasqualetti G.T.Dati srl Tel. 0557310862 - 3356172731 - Fax 055720143 Gabriele Bulfon <[EMAIL PROTECTED]> Inviato da: [EMAIL PROTECTED] 04/09/2006 09.35 Per bacula-users@lists.sourceforge.net CC Oggetto [Bacula-users] Spooling Hello, I worked with Bacula spooling to see the effects on Sparc 280R machines (that continue to work very slow without spooling, almost 1000K/s). I tried with different spooling dimensions (10Mb, 100Mb, 250Mb), the result was almost the same: during a single job backup, speed increased to almost 5000K/s. BUT : at the end of the job, a final step of Bacula (kind of spool flushing) last a lot of minutes, and during this step, the medium transfer rate decreases. The final result is then again a medium of 1000K/s... How should I size the spooling dimensions? Is there any way of calculating the correct size? What is that last step lowering the total rate? May I assume that having 2-3 long jobs, this last step well have a little influence on the total rate? Gabriele Bulfon - Sonicle S.r.l. Tel +39 028246016 Int. 30 - Fax +39 028243880 Via Felice Cavallotti 16 - 20089, Rozzano - Milano - ITALY http://www.sonicle.com ------------------------------------------------------------------------- Using Tomcat but need to do more? Need to support web services, security? Get stuff done quickly with pre-integrated technology to make your job easier Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642 _______________________________________________ Bacula-users mailing list Bacula-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bacula-users ------------------------------------------------------------------------- Using Tomcat but need to do more? Need to support web services, security? Get stuff done quickly with pre-integrated technology to make your job easier Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642 _______________________________________________ Bacula-users mailing list Bacula-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bacula-users
