-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Scott Marlowe wrote: > On Mon, 2006-08-07 at 16:09, Ron Johnson wrote: >> -----BEGIN PGP SIGNED MESSAGE----- >> Hash: SHA1 >> >> Scott Marlowe wrote: >>> On Mon, 2006-08-07 at 15:18, Ron Johnson wrote: >>>> -----BEGIN PGP SIGNED MESSAGE----- >>>> Hash: SHA1 >>>> >>>> Scott Marlowe wrote: >>>>> Oh, I see where you were headed. >>>>> >>>>> I've found a bit here and there googling about for multiplex and tar, >>>>> and found an IO:Multiplex module for perl. >>>>> >>>>> I don't see why someone couldn't make use of it to create some kind of >>>>> system where you'd do: >>>>> >>>>> pg_dump dbname | perl mulitiplexscript device1,device2,device3,devicen >>>>> >>>>> No need for postgresql to support it directly. Restoring would likewise >>>>> just be a reverse operation. >>>> Interesting. Many thanks. Scary though that it hasn't been touched >>>> in 30 months. >>>> >>>> With multiple SCSI cards, each with it's own tape drive, this >>>> immensely speeds up the backup operation. >>> Yeah, I read the description, and I think it's just a fancy name for >>> tee. sigh. Not REAL multiplexing, but stream duplication. >> This is where a multi-threaded pg_tapedump would be more effective, >> since it would be able to, for example, have 4 threads reading >> (different parts of) the database and writing to 4 separate tape drives. > > Actually, I kinda prefer the idea of creating multiple streams using > something like RAID, where if you have two streams, it's a mirror, if > you have three or more then you rotate around a parity stripe like RAID > 5. Then, any error on any one tape drive could be recovered. Veritas > has something like that for tape drives. > > Heck, the more I think about it, the more I think it would be an > interesting project for a device driver that was like /dev/mdt or > something, and re-used the md libs from the hard drive universe. > > Attach X tape drive, put in a bunch of tapes, and just pg_dump > mdt0 > and you're backing up. Restore the other way around. Tape RAID? I like that!!!! If the disk system can keep the tape system full, though. - -- Ron Johnson, Jr. Jefferson LA USA Is "common sense" really valid? For example, it is "common sense" to white-power racists that whites are superior to blacks, and that those with brown skins are mud people. However, that "common sense" is obviously wrong. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.3 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFE17dQS9HxQb37XmcRApZIAKCJDCErL0s/MecjFv+jX4YzNzHuVACeLDoT 1BUxLkwU1GBvFzmvms7dWRU= =h7Wq -----END PGP SIGNATURE-----
