The developers at Cabletron Systems, all those years ago, were well ahead of the game when building the fundamental architecture of the original spectrum. A truly event driven object oriented distributed knowledge based system. Being event driven they were able build a threading architecture in their code well before multiprocessor systems were common place and certainly before multi core processors. From the OS view point SpectroSERVER was a single process, from the application perspective there were multiple threads available for performing many different functions. If you 'kill -USR1' your SpectroSERVER process you will get a moot.trace file the shows you all the these internal threads and what they are upto. As spectrum and the available technologies have developed Cabletron, Aprisma and now CA have extended this design, but many of the core workings still remain untouched. It seems that whilst the code is designed around multithreads, moving it to use native OS threading which would allow it to thread over multiple processors is a non trivial task. In V9 they had to rewrite the SNMP polling function to natively support v3 and more importantly v2 as the 32 bit counters in v1 don't really allow for accurate load thresholding in gigabit environments, whilst there is support in earlier versions via the 3rd party SDManager it didn't offer enough functionality. The rewrite has enabled CA to move to native threading for polling. I don't have I full understand of the entire internal architecture, just years of using Spectrum and observing its behaviour plus various discussions with support. I do know there are plans to move more features to native threading, but that in itself has its issues, in v9 we have encountered many bugs causing SS to hang, a result of changes in the threading architecture and the use of native threads, CA assure me they are now getting a handle on these challenges and 9.1 should be more stable.
Rory ________________________________ From: nikhil mehra <[email protected]> To: Barr, Rory: IT (LDN) Cc: spectrum <[email protected]> Sent: Thu May 14 00:38:57 2009 Subject: Re: [spectrum] Server size Rory, I am trying to understand more from architectural point of view, as far as my understanding goes. Spectrum is a multi threaded system from its client prospective, like one click/SRM, SSAPI etc, but when it comes to it internal architecture it is just single threaded: my questions: 1. Do you have idea while accesing SSdb is it again single threaded? 2. Do you have idea while accesing DDM is it again single threaded? 3. Spectrum SNMP/ICMP communication to infrastructure components (servers/routers etc) is through DCM is it also single threaded. 4. What is the architecture change in v9? Can you explain more in detail. 5. What kind of advantage the designers would have got by designing it as single threaded, or its just design at (whatever time they would have designed it) Regards, Nikhil On Wed, May 13, 2009 at 6:07 AM, <[email protected]> wrote: Spectrum has its own moot threading system, this means that the application is multithreaded, but at the OS level it just uses a single native thread and as sucn only uses a single CPU. For this reason clockspeed is your friend and unfortunately whilst the T5120 are nice servers each processor is relatively slow and you are going to run out of SpectroSERVER capacity fairly quickly. This is the main reason we have switched to Linux. The intel platforms have fewer cores, but much faster processors. V9 is slightly better as CA are moving away form their moot threading and using more native threading. For example all of the SNMP polling inv9 uses native threading. Our experience is that this does not give much additional performance as the majority of the CPU is still attributes to one thread. Also we have a number of tickets open around SNMP issues in v9 that might be related to this move to native threading. Regards, Rory -----Original Message----- From: Hofmann, Berthold [mailto:[email protected]] Sent: 13 May 2009 08:57 To: spectrum Subject: [spectrum] Server size Hello all, we have about 1800 device models, and 120 000 models. When I generate a Health Report in Pview, I get the following message: The SpectroSERVER is currently running at full capacity and no other models or additional work should be introduced. Steps should be taken to minimize the current workload or some of the models/work may have to be moved off to an additional SpectroSERVER. SPECTRUM support can perform a sizing to verify that your machine configuration is adequate for your existing database. Spectrum is running on a sun T5120 with 16 Gbyte Ram. Is this a problem of the machine, because it has 64 virtual CP���s but only one is normally used by spectrum, or is this caused by a limit in spectrum. Has anyone more devices on one spectrum server, and what is the hardware? Best Regards Berthold Hofmann *********************************************** Siemens AG --- To unsubscribe from spectrum, send email to [email protected] with the body: unsubscribe spectrum [email protected] _______________________________________________ This e-mail may contain information that is confidential, privileged or otherwise protected from disclosure. If you are not an intended recipient of this e-mail, do not duplicate or redistribute it by any means. Please delete it and any attachments and notify the sender that you have received it in error. Unless specifically indicated, this e-mail is not an offer to buy or sell or a solicitation to buy or sell any securities, investment products or other financial product or service, an official confirmation of any transaction, or an official statement of Barclays. Any views or opinions presented are solely those of the author and do not necessarily represent those of Barclays. This e-mail is subject to terms available at the following link: www.barcap.com/emaildisclaimer. By messaging with Barclays you consent to the foregoing. Barclays Capital is the investment banking division of Barclays Bank PLC, a company registered in England (number 1026167) with its registered office at 1 Churchill Place, London, E14 5HP. This email may relate to or be sent from other members of the Barclays Group. _______________________________________________ --- To unsubscribe from spectrum, send email to [email protected] with the body: unsubscribe spectrum [email protected] -- Nikhil Mehra "The only Constant in Life is CHANGE!" "Whether it is mainframe, client-server, distributed, grid or web services computing ��� none of it works without the network." _______________________________________________ This e-mail may contain information that is confidential, privileged or otherwise protected from disclosure. If you are not an intended recipient of this e-mail, do not duplicate or redistribute it by any means. Please delete it and any attachments and notify the sender that you have received it in error. Unless specifically indicated, this e-mail is not an offer to buy or sell or a solicitation to buy or sell any securities, investment products or other financial product or service, an official confirmation of any transaction, or an official statement of Barclays. Any views or opinions presented are solely those of the author and do not necessarily represent those of Barclays. This e-mail is subject to terms available at the following link: www.barcap.com/emaildisclaimer. By messaging with Barclays you consent to the foregoing. Barclays Capital is the investment banking division of Barclays Bank PLC, a company registered in England (number 1026167) with its registered office at 1 Churchill Place, London, E14 5HP. This email may relate to or be sent from other members of the Barclays Group. _______________________________________________ --- To unsubscribe from spectrum, send email to [email protected] with the body: unsubscribe spectrum [email protected]
