Paul, Your understanding regarding killing is the same as mine...but Doug is always welcome to weigh in on anything he feels like doing so :)
On Wed, Jun 12, 2013 at 1:18 PM, Campbell, Paul (Paul) <p...@avaya.com> wrote: > ** > > This is where Server Statistics are your friend, as you can watch the > thread count growth over time to get an idea of peak thread counts, watch > the growth, Identify times when more threads are needed (End of month List > Count Jumping up for reports), etc. We found that when we moved from a > Solaris 9 zone to a physical Linux server, our initial thread counts at > startup was way too high, as the counts never really grew above the initial > numbers, we set the start numbers lower without changing the max numbers > and got much better performance.**** > > ** ** > > About the destroying of threads, if I remember correctly, once a > List/Fast/Escalation thread is created, it is not destroyed until a server > restart (barring a thread crash) because of the cost of destroying the > thread and then needing to recreate it later was greater than leaving it > idle, Keep me honest here Doug Muller.**** > > ** ** > > *From:* Action Request System discussion list(ARSList) [mailto: > arslist@ARSLIST.ORG] *On Behalf Of *Steve Kallestad > *Sent:* Wednesday, June 12, 2013 3:02 PM > *To:* arslist@ARSLIST.ORG > > *Subject:* Re: How much RAM does an AR System thread use?**** > > ** ** > > ** **** > > I don't know the details of AR System threading, and I might be stepping a > bit outside my bounds of knowledge but...**** > > ** ** > > I agree with Sean that the memory usage for a particular thread when > spawned should be insignificant.**** > > ** ** > > The more threads are active on a given system, the more the OS needs to > cycle through each thread to see if it is ready for processing. Modern > CPUs are capable of managing multiple threads simultaneously, but the limit > of how many can truly be processed at any given time is pretty small.**** > > ** ** > > When the limit is reached, the OS will iterate through the running threads > based on priority.**** > > ** ** > > With the AR System, the number of threads that you have will increase > performance up to the point where you hit the limit and start to see a > diminished in performance because the CPU is spending more time selecting > threads than processing them.**** > > ** ** > > That's a little bit simplistic and doesn't really account for blocking / > interruption / IPC, but it's at least a simple understanding.**** > > ** ** > > The AR System separates it's types of configurable threads into a few > different purposes - Fast / List / Admin / Private / etc.**** > > ** ** > > It's been quite some time since I've had to do thread configuration for > performance purposes, but if you want to go beyond the basic > recommendations it's more a matter of your traffic patterns than anything > else. You want to have a balance between the number of idle threads and > your end user's activity. Idle threads are created ahead of time so end > users don't perceive a performance issue because new threads are being > created. Thread logging will show you when threads are being created and > when threads are destroyed because they are idle or when there's an > unrecoverable error. If I'm not mistaken, Misi has a tool to analyze and > make recommendations for thread counts.**** > > ** ** > > Sun used to produce numbers for how many threads an individual CPU could > reasonably process. I don't think Intel ever put out those numbers and I'm > not sure Sun does anymore.**** > > ** ** > > I honestly think this is a much lower priority issue these days than it > once was. You could do some testing by looking at memory usage at startup > for an arserver with various thread counts and run performance tests, but > personally I don't look at optimizations like this unless I'm experiencing > a problem or I'm going through a formal performance optimization cycle. > There is always the strong possibility that your end user activity will > change, and it will change from day to day and week to week. If you try to > squeeze out every ounce of performance from a system at the end of the > month when everybody is running reports, your configuration is going to > look a lot different than if you tried to do the same thing on the 7th.*** > * > > ** ** > > I could be remembering wrong, but I think once upon a time the queues were > processes and not threads (way back in the 90s). I could be thinking of > apache httpd, but I think ars did the same thing. At that point > optimization of queues was a much bigger deal.**** > > ** ** > > Just my two cents. Not sure that I added much to the discussion :).**** > > Steve**** > > ** ** > > ** ** > > On Wed, Jun 12, 2013 at 11:36 AM, Longwing, Lj <llongw...@usgs.gov> wrote: > **** > > ** **** > > I think the question was based on Remedy/Peregrine/BMC's long standing > statement of**** > > ** ** > > "You don't want to allocate 'too many' threads, because each one comes > with a memory/cpu cost, so your thread counts need to be a > perfect balance to allow proper performance, but not utilize too many > resources"**** > > ** ** > > So, from that standpoint, it's a fair question of "ok...what is the 'cost' > of each thread so I can figure out if I have enough resources to handle the > cost"**** > > ** ** > > On Wed, Jun 12, 2013 at 12:29 PM, Garrison, Sean (Norcross) < > sean.garri...@fiserv.com> wrote:**** > > ** **** > > It was my understanding it uses a shared pool of memory. Each thread > probably uses a small almost insignificant amount except when large queries > are run, etc. If it runs right you will see it double in memory during > caching scenarios and go back down to ~1-3 gig. **** > > **** > > Sean **** > > **** > > *From:* Action Request System discussion list(ARSList) [mailto: > arslist@arslist.org] *On Behalf Of *Rick Cook > *Sent:* Wednesday, June 12, 2013 1:44 PM > *To:* arslist@arslist.org > *Subject:* Re: How much RAM does an AR System thread use?**** > > **** > > ** **** > > I meant how much does each thread allocate, not the entire AR Server. **** > > Rick**** > > On Jun 12, 2013 9:37 AM, "Sanford, Claire" < > claire.sanf...@memorialhermann.org> wrote:**** > > ** **** > > Mine uses between 1 and 1.2 GB**** > > **** > > **** > > **** > > My other answer is totally off topic….**** > > **** > > **** > > I saw this subject line and immediately this came to mine - How much wood > would a woodchuck chuck if a woodchuck could chuck wood?**** > > **** > > -------------------------**** > > From: Action Request System discussion list(ARSList) [ > mailto:arslist@ARSLIST.ORG <arslist@ARSLIST.ORG>] On Behalf Of Rick Cook** > ** > > Sent: Wednesday, June 12, 2013 11:29 AM**** > > To: arslist@ARSLIST.ORG**** > > Subject: How much RAM does an AR System thread use?**** > > **** > > ** **** > > I remember hearing a number some years ago, but it probably has changed > since then. Trying to balance hardware availability with resource > requirements. **** > > Rick**** > > **** > > **** > > _ARSlist: "Where the Answers Are" and have been for 20 years_ **** > > **** > > _ARSlist: "Where the Answers Are" and have been for 20 years_ **** > > _ARSlist: "Where the Answers Are" and have been for 20 years_ **** > > _ARSlist: "Where the Answers Are" and have been for 20 years_ **** > > ** ** > > _ARSlist: "Where the Answers Are" and have been for 20 years_ **** > > ** ** > > _ARSlist: "Where the Answers Are" and have been for 20 years_ **** > _ARSlist: "Where the Answers Are" and have been for 20 years_ > _______________________________________________________________________________ UNSUBSCRIBE or access ARSlist Archives at www.arslist.org "Where the Answers Are, and have been for 20 years"
