Tek-Tips is the largest IT community on the Internet today!

Members share and learn making Tek-Tips Forums the best source of peer-reviewed technical information on the Internet!

  • Congratulations Mike Lewis on being selected by the Tek-Tips community for having the most helpful posts in the forums last week. Way to Go!

kernel tuning parameters streams etc SCO 5.0.5 openserver

Status
Not open for further replies.

smcclen

IS-IT--Management
Feb 27, 2002
5
0
0
US
I have a new compaq proliant ml370 with dual 933, 256m mem. 3-10k rpm wide ultra3 scsi drives(compaq) on a compaq 431 smart array controller. I am running sco openserver 5.0.5a. with SMP and have applied baseline patches RS505A, oss497c, and oss600a. This ought to be plenty fast enough to run an i/o intensive 5 user pharmacy app. However the problem is when one person does a query in the app the sar readings go to 30-50% waiting on i/o. What different kernel parameters would affect this and how can i get a list of parameters and what they actually do. I have been all over the caldera/sco website and sent a query to compaq with no response yet.
 
You've swatted a fly with an h-bomb.


The System Performance Guide in your on-line documentation (life buoy icon) discusses all tunables.

Some general advice at but my guess (in order of likelihood) is:

Compaq Crap (an affectionate term for the add on software like the Compaq Wellness monitor etc) gumming up the works.

The Raid cache is set for write through.

SMP is screwinmg you up (you surely don't need it- it can't be helping, so you ought to try without it)

You are using raid 5 on a heavily write intensive app.

The app is broken.

The raid is broken.

You are imagining it all




Tony Lawrence
SCO Unix/Linux Resources tony@pcunix.com
 
I agree....we sell a 15-20 user inventory system on a ml350 single processor system w/ 256mb 2x 9GB 10K drives on a LC2 raid controller. We only use raid 0+1 mirroring and this is fast enough for all but the most intensive processes.

Any system slow downs or loads are a function of our application (usually improperly structured transactions or queries) and will show up in the sar wio column. This is also a result of everything else in the system running fast enough that the only thing the system does wait on is disk i/o.

Do you use a database engine? Do they reccommend any kernel changes?
One of the main changes to improve i/o we have made has been to set:
NBUF = 32768
NHBUF = 8192
MAXBUF = 32768

Now this does have some risks if the system dies mid write but we minimize this with before and after imaging on the database (this is a feature of the particular database we use {progress}). I will also assume you have a UPS on the system but things other than power can shut a system down just as quickly and with as much damage.

Lastly you may want/need OSS471 Pent microcode update.

stan hubble

 
Tony and Stan. I will address both of your points at once.

Let me start by saying when I said a five user system that was probably misleading. There are 5 terminals and each terminal has 2-4 logins running depending on the quickness of the pharmacists or tech running it. Each of these session may be idol or running transactions simultaneously. Also let me add that I am a programmer by background. I can program in a variety of Basic products, COBOL, DBASE(Clipper), and Progress (I specilize in database application development for windows based PC's but i have been programming in progress on unix (AIX and SUN solaris for 8 years. mostly maintenance programming though)
Just FYI so you know where I am coming from. Now to the situation at hand.

1) Since I am running sco in a text mode. Where do I find this "LIFE ICON BOUY"? I have gone again thru the sco.com site and found all the doc pages lead to dead ends. I have a sco media pack and can not find anything on them. (granted I could be a complete idiot) BUT that being said where do i find the "SYSTEM PERFORMANCE GUIDE" on-line.
Stan i have already made those changes as far as buffer options go but i am just quessing at numbers because AGAIN i do not know what all the options are.

2) Can I turn off the "COMPAQ CRAP" without making the system unstable?

3) The Compaq 431 controller does not allow write cache

4) This is the first multi-processor machine I have setup or SCO. Will SCO recognize and utilize both CPU's without SMP installed?

5) I am using raid(5) and the system is heavy writing app. using custom btrieve tables. There is one table about 750meg and at least ten others that are over 250 meg, with a total of 60-70 other active tables. Of course that does not include indexes. I have never like the mirrored invironment. All 3 mirrors systems i have tried have corrupted the mirror as well as the original and i end up with total data loss outside of backups. So raid one has not be high on my list.

6) The app is only broken by means of bad i/o programming.

7) The raid seems to be running fine. going into the smartstart array config. shows no errors in the diagostics or logs. However I do not know how to ensure it is running the scsi3 mode instead of scsi2. Under hwconfig I show
the drivers running for scsi2 but that could be that compaq loaded them up because that is what the default controller is for the ML370 and it is onboard(not removable). However I do not see anything about Ultra3.

Hope I did not get to overwhelming for you all. And thanks again for you time and help.

Steven P. McClenathan
 
Too many questions :)

No, you do NOT get any SMP without installing and licensing SMP.

is your perfance guide online.


Yes, you can shut off the Compaq stuff to see if it is the source of your grief.

I have to go eat dinner now- I've been running around since 4:00 AM and no lunch (is black coffee lunch?) so please forgive me if I missed anything or answered too hastily.

Tony Lawrence
SCO Unix/Linux Resources tony@pcunix.com
 
Thanks Tony. Go eat I've been and will be there again.

As far as SMP goes I thought you where suggesting taking it out in your first reply but then I would lose my 2nd CPU capabilities.

I went to that sight and got "cannot display this page" message. Same as i had gotten when I was previously there. Is that page for only a certain level of support?

Do I shut the Compaq stuff off through scoadmin or from smartstart?

Steve
 
Yes, if you uninstall SMP your system won't use the 2d CPU. It won't use it anyway if your load average isn't over 1.0.

Check sar -q - if it isn't consistently over 1.0, SMP is doing nothing but slowing you down.

But even if it is over 1.0 try it without SMP anyway- you may find that is the source of your problem.

Find the Compaq stuff out of /etc/rc2.d. Most of those scripts will take a "stop" argument:

/etc/rc2.d/S83COMPAQWHATEVER stop

f you find that one is your problem, just stick an "exit 0" at the start of the appropriate scripts to disable them permanently.

I don't know why you can't access that page.
Tony Lawrence
SCO Unix/Linux Resources tony@pcunix.com
 
Status
Not open for further replies.

Part and Inventory Search

Sponsor

Back
Top