>>> <david.partri...@perdrix.co.uk> schrieb am 27.03.2017 um 18:03 in Nachricht <bba1ec78-a602-4d57-97cb-c077927cf...@googlegroups.com>: > I'm connecting my Linux server to an LTO-4 tape drive over a 1 gigabit LAN > with very little other activity. > > Doing some hand waving, I guess that I should allow ten bits per byte and a > protocol overhead of around 40%. That gets me to about 60MB/s which I know > is about half what the drive is capable of. > > However what I'm seeing is a consistent throughput of about 30MB/s which is > quite a lot slower that I'd expect. > > The processor is an Intel Atom D525 1.80Ghz four core processor with 4GB > RAM.
Hi! I may be old-fashioned, but did you listen to the drive? Is it possible that the drives does to stop-and-go mode where it has to rewind to re-capture the last position periodically? I know that some drives can adjust their peeds to transport bandwidth, but some drives always operate at full speed, forcing them to stop and go. Also: Did you try to write directly from dd to the tape (being able to control the block size)? Regards, Ulrich > > The drive I'm backing up is a SATA SSD. > > The backup is run thus: > > sudo mt-st -f /dev/st0l setblk 65536 > sudo dd bs=64k if=/dev/sdb | mbuffer -s 65536 -m -m 50% -P 80 -o /dev/st0l > > Is what I'm seeing pretty much the norm, or is there something I can do to > get better throughput? > > Thanks in advance for any assistance you can provide. > Dave > > > -- > You received this message because you are subscribed to the Google Groups > "open-iscsi" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to open-iscsi+unsubscr...@googlegroups.com. > To post to this group, send email to open-iscsi@googlegroups.com. > Visit this group at https://groups.google.com/group/open-iscsi. > For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups "open-iscsi" group. To unsubscribe from this group and stop receiving emails from it, send an email to open-iscsi+unsubscr...@googlegroups.com. To post to this group, send email to open-iscsi@googlegroups.com. Visit this group at https://groups.google.com/group/open-iscsi. For more options, visit https://groups.google.com/d/optout.
