Hi, This is not strickly an question pertaining to the list but I'm sure some of you have faced this issue: I just got a new ArcVault24 librarie with 2x LTO-3 tape drives and searching through the amanda archives I found posts that claim that the default amanda 32k tape blocksize is not really optimum for that sort of drive if I want to avoid shoe-shining.
Hardware: I've setup the default access device to the drives as non-compressing. The library is hooked through a LSI U320 PCI-X scsi card to a 4 DualCore2 Xeon with 8GB of RAM running Debian/Etch running a 64bit kernel 2.6.21.5-i686-64-smp. It should be beefy enough :) Running amtapetype with different blocksize gives me ~386MB for capacity (close enough to 400MB) but I never seem to get close to streaming: bs= speed= 32k 50482 kps 128k 50531 kps 256k 50508 kps 512k 50521 kps 1024k 50512 kps 2048k 15780 kps 4096k 15875 kps Any hint on what I should try next? And finally: is there a utility on Debian or Linux in general that would allow me to see the IO transfer rate to character devices. I know how to do this on Irix but dunno if it exists in the Linux universe. (gratis irix trick: start osview and look for 'phread' and 'phwrite' in the menu 'Other'. They give the aggregated physical IO transfer rate to all character devices) thanks jf -- <° ><
