I'm aware that many of you are experiencing some slow problems and error messages with the server. I've been babysitting it all night to watch the performance monitors and such. I've opened a ticket with the people who make the software and we're giving it until tomorrow night to see if things settle back down. If not, we'll probably be looking at some minor server hardware upgrades.
The forum server is a dual-550Mhz machine with 384MB of memory, dual SCSI-3 9.1GB hard drives, and runs Linux kernel 2.2. It's pretty hefty, but there is a little room for improvements. I *think* that disk performance is the current bottleneck. UBB uses flat files to store the messages, so it is very disk intensive. If that proves to be true, we'll go to a SCSI RAID5 setup. That would increase disk performance by about a factor of 6x using Adaptec's 3400 controller and 3 of Seagate's new Cheetah 15,000 rpm drives. We would also increase memory to at least 512MB. Infopop, the company that makes this software, went to a system almost identical to that and their performance problems went away.
Just bear with us for a few days and we'll get it straightened out. I think the improvements in the new software are worth whatever we need to do.
I don't mean to step on anyone's toes but I feel obligated to speak up about the RAID setup.
At my last job I upgraded the file server from a non-RAID Sun ultra 1 to a Sun E250 RAID5 setup W/18,000rpm disks. It used software RAID which actually reduced disk performance compared to the old machine. Data redundancy was the ultimate goal & the performance drop was not significant. I'm not sure if a hardware raid controller can match the performance of a regular single disk. There is still a lot of overhead for each disk write. The advertised specs for the raid controller can rarely be matched unless the conditions are ideal.....
Hardware RAID is better than software RAID because software RAID utilizes the system processor(s) while a hardware RAID controller, like the Adaptec controller Jason is talking about, has its own processor(s). Using the system processor(s) to perform RAID functions reduces the amount of time the processor(s) have to allocate to other processes. By using a RAID controller, the processor(s) on the controller handle the functions of reading/writing to the disks. Dan, that is probably why you noticed a decrease in performance.
Jason, you are probably right when you say that performance might be the bottleneck. Just out of curiosity but how do you have the current disks set up? I don't know that much about Linux but the reason that I ask is you might consider using a separate disk for the operating system and pagefile (if any) as if those are on a fault-tolerant drive that could lead to a performance degradation. Also, depending on how old the current drives are, you might be better off with the newer drives because of a larger cache on the disks.
A configuration that you might try is to use either one or both of the 9.1GB drives as an operating system/program files/pagefile drive and then do the RAID-5 upgrade for the forums. If you do get those 15,000 RPM drives, be sure to keep them cool. [img]images/icons/cool.gif[/img] Also, the more RAM, the better. You can never have too much. [img]images/icons/cool.gif[/img] [img]images/icons/laugh.gif[/img]
Of course this is all $$$ and I don't know how much you want to drop into an upgrade.
Cheers and I hope I didn't step on anyone's toes,
Dave
__________________ 1996 F-350 XLT CC SRW 4x4 with plenty o' Redneck Bling: APCM●BTS-E4OD●4L10●MADDOG injectors●Hypermax H2E, intercooler, & exhaust●TYMAR intake & HPX●TSM disc brakes●Hydro-Boost●International water pump●215 amp generator●CCV re-route●285/75R16 Wild Country XTX tires●Centramatics●Denon DCR-830RD & DCH-520 203,000 happy miles DZLJIM 3:16 ~~NTxPSA - Hold my beer and watch this.~~
I am glad I got through long enough to read your message, I have hardly been able to get into the forums and once in I get stuck not able to go anywhere. Good luck, hope you are able to fix things. As you can tell I'm not computer literate [img]images/icons/laugh.gif[/img]
MaryAnn
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99 F250 SD XLT SC, Dark Hunter Green, ingintion override, Western Diesel triple A-pillar gauges, air horns, 4" Dynomax Exhaust, WD Ram Air, Lund Hood Scoops,Putco SS vertical grille, tow 34' Jayco 5er
<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by JLester: None ever see a load like the forums server does though.<HR></BLOCKQUOTE>
That's cause big loads mean nothing to the PSD crew. We're truckin' [img]images/icons/smile.gif[/img]
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Bilge Rat Association member with Ninja Wife
I gotta beg to differ a little on the RAID solution. RAID0, or striping, can help with both read and write performance. RAID5 on the other hand, can have a radical hit on write performance.
Remember that the mission of Redundant Array of Independent Disks is to provide redundancy and allow the application to keep running even when there is a loss of a single spindle (I am excluding RAID0 since that technically isn't a redundant array [img]images/icons/smile.gif[/img] ).
In a RAID5 configuration, there are at least two physical writes for every logical write. At least one write for the "writer" and a second write for the checksum to maintain the redundancy. These can end up being more than this if the chunksize is poorly set in relationship to the size of the I/O. Key to the successful performance of a RAID implementation is a sizable cache along with write-back (rather than write-thru) caching (at the hardware level, independent of any caching relating to the system or processor cache).
If it's a read intensive application and caching is suitable, then RAID5 might be a performance win, but I don't consider it a guarantee.
Roakey can probably also add to this but I have spent a considerable amount of time understanding RAID solutions and their relationship to database files. [img]images/icons/smile.gif[/img]
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00 250 XLT SD SC 4x4 PSD auto, Bright Amber
USEF, USDF, RMDS, USPSA (Life), EPCSO Volunteer
So many toys... so little money... :-)
Dittos on Raid 0. We just upgraded our office server to raid 0 on the new Asus a7v-133 MB with only a single Athlon 1200. It is mucho better just using ibm 7200rpm Ide drives. No redundancy but the onstream backup takes care of that. [img]images/icons/laugh.gif[/img]
FYI, These are new error messages I'm getting.
Software error:
Callback called exit.
For help, please send mail to the webmaster (webmaster@ford-diesel.com), giving this error message and the time and date of the error. Content-type: text/html
Software error:
END failed--cleanup aborted at /var/www/cgi-bin/ubbcgi/ultimatebb.cgi line 676.
For help, please send mail to the webmaster (webmaster@ford-diesel.com), giving this error message and the time and date of the error.
Keep up the good work. It'll get better [img]images/icons/cool.gif[/img]
Still the problem with RAID 0 is you loose a drive your down until you get a new one and restore the os and data from tape. If you don't have another drive laying around you'll have to wait. RAID 5 is simular but if you loose a drive you have time to hot swap one in (in many cases). It's a down time issue.
In Dan's case maybe they were using RAID 1, disk mirroring is the safest, you'll pick up some read time but get hurt on the write time.
Linear Mode
