Hi Janet,
I'll have a go at it, don't hang me up on the numbers though.Judging from your
current settings , you're running against an Oracle DB , so you can only have 1
DB connection / DB worker process.
so we got a 1000 regular users and 70 admins
first, let's say the admins are twice as active as the normal ones. This gives
1140 user, which rounds up to 1200.
1200 users.
I'm assuming around 0.5 seconds average processing time / request
we want around 2 seconds for average response time
so 1 thread can virually handle 4 concurrent clients
1200 users send 1 req. every 10 seconds
so that's 120 req/s
we will need 120/4= 30 threads to handle those
We will want 30 CPw threads , and 30 DSw threads
So, for the CP : 2 CPw , 15 clients/w
So, for the DS : 30 DSw , 1 clients/w
make sure the workers are all in their own process, which is also the case for
the PE service. That should do it, at least , if the assumptions are correct and
the hardware can handle it.
hth.
Cheers,
Edwin.
Quoting [EMAIL PROTECTED]:
>
>
> Hi Lidia, thanks for the doc. It would be great if it could include a real
> world
> example!
>
> Would anyone like to take a stab at offering some # based on my scenario:
>
> - 1000 users will be using this app mainly between 7AM-7PM
> - most all of them will be using it on a daily basis to fill out their
> timesheets,
> - 70 ADMIN users will be heavier users approving time charges weekly, and
> creating & budgeting workplans, and running reports.
>
> Our current CP Service settings of:
> # of workers = 2 (running out of process)
> Max # of clients per worker = 4
>
> do seem rather low to me. But what might be more reasonable?
> My uneducated guess:
> # of workers = 5 (running out of process)
> Max # of clients per worker = 10
>
> And for the RDBMS Service, we currently have:
> # of workers = 16 (running out of process)
> Max # of clients per worker = 1
> max # DB connectoins per process = 25
> max # DB connections per DB = 25
>
> Any comment on how they look?
>
> Thanks very much for your help!
> Janet
>
>
>
>
> (Embedded
> image moved Lidia Marchioni <[EMAIL PROTECTED]>
> to file: 11/11/99 06:44 PM
> pic05200.pcx)
>
>
>
>
> To: Janet Traub/IS/SSC/THD
> cc: nd4 forum
> <[EMAIL PROTECTED]>
> Subject: Re: [ND] No Free workers
>
>
>
>
> Just to confirm:
>
> "No free workers" indicates that the (# cp workers * max clients per CP
> worker)
> has
> been exceeded. Under normal circumstances, this should only occur if the
> number
> of
> concurrent clients accessing the system exceeds the above number.
>
> and here, mostly from the ND5 documentation:
>
> Tuning the Worker Pool
> For important services such as the Connection Processor and Data Service,
> the
> NetDynamics Command Center allows fine grained tuning of the worker pool.
> For
> each
> component there are three properties that can greatly affect system
> performance:
>
> 1 NumberOfWorkers: dictates the size of the worker pool.
>
> 2 MaximumClientsPerWorker: indicates the maximum number of clients that can
> simultaneously access a single worker instance.
>
> 3 NumberOf Processes: indicates the number of processes over which the
> workers
> are
> distributed.
>
>
> Here are some general rules of thumb and observations about these
> properties:
>
> 1 CP Workers will always be out-of-process. In a deployment operation,
> workers
> should
> run in their own process for both performance and fault tolerance (for
> example,
> a CP
> worker running a project can crash and bring down the entire server if it
> is
> running
> in the same process as the SM).
>
> 2 Usually there will be only a single CP worker per process (namely
> NumberOfProcesses
> equals workers). The NetDynamics services (the CP and DS) are designed so
> that
> there
> is no reason to run multiple workers in a single process. Instead the
> MaxClientsPerWorker should be tuned, and each worker should run in its own
> process.
>
> 3 MaxClientsPerWorker * number of workers per process dictates the number
> of
> threads
> that will be running in a process. Depending on your system and how it
> context
> switches, it may be better to have many concurrent processes than many
> concurrent
> threads. For example, 1 worker with a max clients of 100 indicates that 100
> threads
> could potentially be active in the worker process. On the other hand, 10
> workers
> with
> 10 clients each indicates that only 10 threads will be active in each
> worker
> process.
>
> 4 NumberOfWorkers * MaxClientsPerWorker dictates the maximum number of
> clients
> that
> can simultaneously access the component. This is important. If there are 2
> workers
> and 5 clients per worker for the CP service, then only 10 CGI clients can
> access
> the
> system in parallel. (The other clients will wait for a free worker to
> become
> available.) On the other hand, if there are 5 workers and 100 clients per
> worker, 500
> concurrent clients (and potentially 100 concurrent threads per worker) can
> be
> supported; however, depending on the hardware, 500 concurrent clients may
> actually
> degrade performance due to thrashing and thread context switching.
>
> 5 Ratio of CP MaxClients/DS MaxClients- You should never have fewer total
> DS
> MaxClients than CP MaxClients. This is because of a reservation revocation
> that
> can
> occur when there are fewer total DS clients than total CP clients. In our
> testing we
> find is best to have 115% more total DS clients than total CP clients.
>
> Lidia
>
>
> [EMAIL PROTECTED] wrote:
>
> > Hi folks, I searched the archives and TechNotes but couldn't find any
> answers
> > about this one
> >
> > We have about 20 users piloting our ND4 app that runs on HP-UX. The ND4
> app
> > server stopped responding today and when I looked in the
> smDefaultPartition.log
> > I saw this message
> >
> > **************SM is started*****************
> > exception CNdNoFreeWorkersException{string reason="no free workers";}
> > at
> >
>
netdyn.cosi.service.loadBalancing.CNdLoadBalancingManager.allocateWorker(Compile
d
>
> >
> > Code)
> > at netdyn.cosi.service.CNdServiceImpl.allocateWorker(Compiled Code)
> > at netdyn.cosi.stubs._tie_INdService.allocateWorker(Compiled Code)
> > at netdyn.cosi.stubs._INdServiceImplBase._execute(Compiled Code)
> > at netdyn.cosi.stubs._INdServiceImplBase._execute(Compiled Code)
> > at com.visigenic.vbroker.orb.SkeletonDelegateImpl.execute(Compiled
> Code)
> > at com.visigenic.vbroker.orb.GiopProtocolAdapter.doRequest(Compiled
> Code)
> > at
> com.visigenic.vbroker.orb.GiopProtocolAdapter.dispatchMessage(Compiled
> > Code)
> > at com.visigenic.vbroker.orb.ThreadPoolDispatcher.run(Compiled Code)
> > at com.visigenic.vbroker.orb.WorkerThread.run(Compiled Code
> >
> > and that "no free workers" junk was repeated 8 times.
> >
> > I chked our CP service settings...and I see we have:
> > # of workers = 2
> > max # clients per worker = 4
> >
> > (Hmnn, 2 x 4 = 8...is that why it was repeated 8 times?)
> >
> > Questions:
> > Does it seem likely that with only 20 total users (and most likely no
> more
> then
> > 10 of them accessing the app concurrently) we would hit a "no free
> worker"
> > problem?
> >
> > Could the scarcity of memory/space on the HP server box contribute to
> this
> > problem?
> >
> > If anyone has a decent understanding of this, could you please shed some
> light
> > on this?
> >
> > Thanks!
> > Janet
> >
> > _________________________________________________________________________
> >
> > For help in using, subscribing, and unsubscribing to the discussion
> > forums, please go to: http://www.netdynamics.com/support/visitdevfor.html
> >
> > For dire need help, email: [EMAIL PROTECTED]
>
> _________________________________________________________________________
>
> For help in using, subscribing, and unsubscribing to the discussion
> forums, please go to: http://www.netdynamics.com/support/visitdevfor.html
>
> For dire need help, email: [EMAIL PROTECTED]
>
>
>
Greets,
Edwin van der Sanden,
NetEd.
web : www.neted.nl
mail : [EMAIL PROTECTED]
mobile: +31-6-55866016
_________________________________________________________________________
For help in using, subscribing, and unsubscribing to the discussion
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