On Thursday 15 August 2002 14:49, John Koenig wrote: >>My motto: Disk is cheap, don't skimp on holding disk. > >Yup... after I deployed a 181 GB drive for our holding disk, I saw >somewhat different behavior in amstatus... though I would have >expected the total time of the backups to drop (compared to a >relatively small 25 GB holding space I used before) they did > not... I conclude this was because the entire run is tape i/o > bound... Holding disk usage on the runs with this disk were about > 90% capacity... so the clients were not taking so long to > complete their data transfers... > >This would seem to indicate I need to double this amount of space > to hold 2 days of backups, currently... I'd like to have a week's > worth, actually.... in case the tape goes South and replacement > is not easy and quick. > >So does the chunksize parameter affect performance in any way?
Only in that it prevents troubles with a filesystem that can't handle large files. There was, at the time amanda was first deployed, a 2gig limit to the filesize in many of its various platforms filesystems. Many of those limits are now historical, but you'd hate to find it out by doing a recovery and having it blow up because a tape of 20gigs was all one big file. >thx -- Cheers, Gene AMD K6-III@500mhz 320M Athlon1600XP@1400mhz 512M 99.11% setiathome rank, not too shabby for a WV hillbilly
