Re: What do you use?
On Wednesday 31 December 2003 02:04 pm, Francisco wrote: On Wed, 31 Dec 2003, Jason Bacon wrote: 3ware IDE RAID. Agree on the 3ware controllers. No such thing as cheap tape backups. :-( If the amount of data can compress into a CD or DVD you could consider a burner. Moreover, although not a replacement for a tape backup or burning to CD/DVD you could also consider having an extra disk outside the RAID for backups. For example to keep multiple days of data on the second disk for easy/quick access. We're using external USB disks for medium-term archival, and various optical media for long-term. DVD-RAM is the most convenient, albeit slow and non-portable (R/W UDF support isn't quite there yet, so we're stuck with UFS for now). With a USB2 interface, the USB disks are pretty fast, and you can't beat the convenience. One has to be very careful with USB disks on Unix, though, since they can be unplugged without warning while the filesystem is mounted, causing serious filesystem damage. I experimented with various solutions (e.g. automounting and unmounting with synchronous write enabled), but nothing gave 100% protection. Our RAID systems (ICP Vortex SCSI and 3ware IDE) are backed up on Mammoth or AIT tapes with autochangers using afio and chio. Not a cheap solution at ~ $10,000, but there's no other way to automatically back up 1/2 terabyte on media that can be easily stored off-site. Good luck, Jason ___ [EMAIL PROTECTED] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: What do you use?
On Thursday 01 January 2004 07:09 am, Francisco Reyes wrote: On Thu, 1 Jan 2004, Scott Mitchell wrote: As for RAID, we use Vinum, but only because I inherited a bunch of machines with hot-swap SCSI bays and no hardware RAID. It works well, once you have it set up, and I've even managed to swap out failed drives without a reboot :-) I'll definitely investigate the 3ware cards when I need to build a : new RAID server, though. But wouldn't a 3ware RAID be slower than an SCSI setup? Unless your current setup is using old SCSI disks. Also how is the load? Lots of simultaneous use or just many quick/small access (ie people using documents/spreadsheets). Well, I'm in a position to provide some comparison data with not-too-many variables, so I felt obliged to run a quick benchmark. The program writes a large file (large enough to overwhelm any memory buffering) using low-level I/O, does an fsync() before closing, and then tests random seek and sequential read on the same file. I watched the system load using top during the benchmark and took a snapshot near the beginning and end of the write cycle. ~ 3ware Escalade IDE 560gig RAID-5 (8 x 80G barracuda disks): Writing 1677721600 byte test file... Done. Time = 58.433367 Performing 1000 random seeks and reads... Done. Time = 0.235705 Performing sequential read... Done. Time = 7.303429 CPU states: 0.8% user, 0.0% nice, 17.1% system, 0.0% interrupt, 82.2% idle Mem: 68M Active, 609M Inact, 279M Wired, 89M Cache, 112M Buf, 960M Free Swap: 4081M Total, 240K Used, 4081M Free CPU states: 0.4% user, 0.0% nice, 13.2% system, 0.0% interrupt, 86.4% idle Mem: 68M Active, 1390M Inact, 279M Wired, 88M Cache, 112M Buf, 180M Free Swap: 4081M Total, 240K Used, 4081M Free ~ ICP Vortex SCA 240gig RAID-5 (4 x 72 gig cheetah SCA disks): Writing 1677721600 byte test file... Done. Time = 53.667167 Performing 1000 random seeks and reads... Done. Time = 0.220799 Performing sequential read... Done. Time = 5.114555 CPU states: 0.4% user, 0.0% nice, 9.6% system, 1.0% interrupt, 89.1% idle Mem: 52M Active, 401M Inact, 274M Wired, 77M Cache, 112M Buf, 1201M Free Swap: 4081M Total, 248K Used, 4081M Free CPU states: 0.4% user, 0.0% nice, 25.1% system, 1.9% interrupt, 72.6% idle Mem: 52M Active, 1601M Inact, 276M Wired, 74M Cache, 112M Buf, 3228K Free Swap: 4081M Total, 248K Used, 4081M Free Both systems are running 5.1-RELEASE, with 2 gig RAM. The 3ware machine has a faster CPU (Athlon 1.6Ghz) than the ICP (dual Pentium 850), but this shouldn't be significant for raw I/O at these CPU speeds. The CPU usage is lower on the ICP system (remember that it has a slower CPU when comparing the CPU loads). CPU use consistently went up toward the end of the write cycle on the ICP system, but stayed flat on the 3ware. I noticed a drastic reduction of CPU load on the 3ware system when we went from 4.5-RELEASE to 4.6-RELEASE CPU load has never been a problem on either server. JB ___ [EMAIL PROTECTED] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: What do you use?
On Friday 02 January 2004 07:19 am, Francisco Reyes wrote: On Fri, 2 Jan 2004, Jason Bacon wrote: Well, I'm in a position to provide some comparison data with not-too-many variables, Thanks much for sharing the results. They seem close enough that someone who is price concious or on a limited budget may want to consider the 3Ware. However, what a test like that may not show well is the difference when having multi-user access. I think on that case the SCSI disks may do better. Actually, I think the test *does* show that. It clearly showed that the SCSI system was somewhat less impacted by RAID access. Hence it would follow that the SCSI system could handle a somewhat heavier load before seeing a performance drop. The choice would depend how much the extra bandwidth is worth to you, assuming your usage patterns could make use of it at times. I can tell you that our users have never complained about performance of the server. We have relatively few users (1-10 at a time) running fairly intense data analysis (on the order of 1 hour total CPU time + processing gigabytes of 3d brain images ) either running on the server or over NFS. If you're wondering how they perform under heavy process loads, note that Yahoo is using the 3ware controllers extensively. Maybe they'd be willing to share their experience... Regards, Jason ___ [EMAIL PROTECTED] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: Mounting CDROM as user under 5.x
If anyone's interested in a programmed solution, you can download my supermounter from http://www.neuro.mcw.edu/~bacon/fmri.html. It runs SUID root (you can change this to SUID whatever you want by modifying the Install script if you're concerned about security) and lets you specify which devices users are allowed to mount/unmount, and whether to automatically eject on unmount. ( Also download the eject program if you want this feature ) Cheers, Jason ___ [EMAIL PROTECTED] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: What do you use?
3ware IDE RAID. Yahoo did the beta testing on these and they perform quite well on anoything above 4.5. No such thing as cheap tape backups. :-( JB On Wednesday 31 December 2003 01:06 pm, Sean Hafeez wrote: I need to build a file server for work. I was wondering what people on the list use for a RAID solution? I would like to stick to an IDE RAID controller. RAID5 or RAID1. Also what do you recommend for a cheap tape backup? And before I forget, pls let me know if you are using it under 4.x or 5.x. I would love to do an external STA type setup but I am sure it is not quite there yet under FreeBSD. Thanks for the info! -Sean ___ [EMAIL PROTECTED] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED] ___ [EMAIL PROTECTED] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
