Re: How to build OpenPegasus SDK as single threaded?

Thank You Kirk, you opened my eyes..!! and it was my bad, I should have
traced down one of the API till its end point.
Now I realize there is no way we can build OpenPegasus SDK as an single
threaded one.

Thank You all, for participating in the discussion.

On 8 April 2012 22:21, Kirk Augustin <[email protected]> wrote:

> I just tried to look at the Pegasus client sample code and did not quickly
> find it.
> I probably deleted it and would have to reinstall.
> But even if the Pegasus client library was multi threaded capable, you are
> not required to have multiple client threads, so it would not matter.
> If you only have one client, and it is not trying to be asynchronous, then
> a multi threaded client library would behave as if single threaded.
>
>
>
> Kirk Augustin
> 11821 NW McNamee Rd
> Portland, OR 97231
>
> HM: 503-289-4356
>
>   ------------------------------
> *From:* Pranav S <[email protected]>
> *To:*
> *Cc:* "[email protected]" <[email protected]>; "
> [email protected]" <[email protected]>; "[email protected]" <
> [email protected]>; "Hwang, Johnny" <[email protected]>
> *Sent:* Sunday, April 8, 2012 3:24 AM
>
> *Subject:* Re: How to build OpenPegasus SDK as single threaded?
>
> Hey, anyone agree with me? need for Single Threaded Pegasus libraries?
>
>
> On 8 April 2012 12:12, Pranav S <[email protected]> wrote:
>
> :-)  It is nice to learn quotes from Confucius... It is nice when you get
> to learn few new things in discussion forums.>!!
>
> On 8 April 2012 12:02, Hwang, Johnny <[email protected]> wrote:
>
>  There's a java version of sblim. Otherwise, if you insist on sticking
> with pegasus, I really doubt that there are other teams out there using
> pegasus as a single-threaded client. Think hatchet for killing a fly on a
> friend's forehead, as Confucius would say.
>
>
>
> Ugh stupid autocorrect
>
>
> Pranav S <[email protected]> wrote:
>
>
> AFAIK, sublim is linux implementation of CIM/WBEM standards for managing
> resources. I do not see the package having support for multiple platforms
> as Pegasus has. And Pegasus has much better implementation.
>
>
> On 8 April 2012 11:35, Hwang, Johnny <[email protected]> wrote:
>
> If you're building a client, take a look at sblim or something like that.
> Pegasus is probably too heavy for your needs.
>
>
> Ugh stupid autocorrect
>
>
> Pranav S <[email protected]> wrote:
>
>
> Hi Kirk,
>
> If single threaded library wants to use a multi threaded one, or assume an
> application binary is linking indirectly to multi threaded one, then the
> entire build chain has to be built with multi threading enabled. Now as I
> am more focused towards writing a client side binary, I am not using any of
> multi threaded piece of code from the Pegasus library. So why should I
> unnecessarily build multi threaded one? and my client binary will be
> performing basic operations like enumerations, listing association kind of
> stuff, and for these operations Pegasus do not create any threads.
>
> I agree on what you are saying if I were to focus on a Provider, which
> will plug into server, serving to the multiple client requests.
>
> I still think we need to have switch to enable/disable multi threading.
>
> On 7 April 2012 23:40, Kirk Augustin <[email protected]> wrote:
>
>  It is unsafe for a single thread to call a multi-thread, but perfectly
> safe for a multi-thread to call a single thread.
> Multi-threading is the only safe way a service like Pegasus can call
> providers.
> If not multi threaded, then one faulty provider can corrupt all providers,
> as well as Pegasus, with an infinite deadlock.
> On HP UX you can mix multi thread and single thread.
>  You just have to careful about singe thread library calling multi
> threaded libraries.
> Multi-threaded libraries have to call single threaded libraries all the
> time.
> A single thread library should always be passed data by value instead of
> reference, so should never need any synchronization protection.
>  That can not possibly be a problem on any system.
>
>  You are using the multi threading piece of code in Pegasus.
> It can not be unused.
>  Pegasus is a remote network, communications systems, server, relying on
> sockets and an unknown number of provider plug-ins.
> It would be virtually inconceivable to imagine a good way that could be
> done without multi-threading.
> You could greatly increase the number of independent processes instead,
> and created more sockets or pipes to try to share data, but multi-threading
> is a much better solution to a multi tasking server like this.
> Your providers are best compiled as out of process, so have nothing to do
> with threading at all.
> Threading is only important within Pegasus.
> The question of threading really is not relevant because Pegasus is in
> control of what it calls, so will do so safely.
> All you have to worry about is your providers.
>
> Kirk Augustin
> 11821 NW McNamee Rd
> Portland, OR 97231
>
>  HM: 503-289-4356
>
>   ------------------------------
> *From:* Pranav S <[email protected]>
>  *To:* Kirk Augustin <[email protected]>
> *Cc:* Devchandra Leishangthem <[email protected]>; "
> [email protected]" <[email protected]>
> *Sent:* Saturday, April 7, 2012 10:37 AM
>
> *Subject:* Re: How to build OpenPegasus SDK as single threaded?
>
> On HP UX we cannot mix single threaded libraries with, multi-threaded
> ones. It might cause undefined behaviour.
> And, if an application links to multi-threaded library directly or
> indirectly, it has to be built with multi-threading (-mt option) enabled.
> As I am not using multi threaded piece of code from pegcommon(src/Common),
> I am expecting it to be disabled. Why unnecessarily create a dependency on
> pthread library? I believe it is good to have a flag in configure files
>  for enabling/disabling the multi-threading.
>
>
> On 6 April 2012 22:00, Kirk Augustin <[email protected]> wrote:
>
>  But if you turned off multi threading in Pegasus, you would create and
> ensure the very condition you are concerned about avoiding.
> You would cause a single threaded library to be linked with multi threaded
> ones.
> The only safe solution is to make sure Pegasus is multi treaded, so that
> you avoid the possibility of a single threaded library being linked to a
> multi threaded one.
> There is no risk in a multi threaded library linking to a single threaded
> one because a single threaded library gets multiple copies.
> Only the other way around is risky.
> There is only one copy of a multi threaded library, and you do not want
> single threaded libraries linking because then more than one could end up
> linking at the same time.
>
> Kirk  Augustin
> 11821 NW McNamee Rd
> Portland, OR 97231
>
>  HM: 503-289-4356
>
>   ------------------------------
> *From:* Pranav S <[email protected]>
> *To:* Devchandra Leishangthem <[email protected]>
> *Cc:* [email protected]
> *Sent:* Friday, April 6, 2012 4:38 AM
> *Subject:* Re: How to build OpenPegasus SDK as single threaded?
>
> I some where read, on HPUX and AIX linking single threaded libraries to
> multi threaded causes undefined behaviour. Hence I was trying to to build
> openpegasus libs as single threaded. I see libpegcommon uses pthread
> library. I would like to know if there is way to turnoff the
> multithreading. In HPUX Makefiles I see "-mt" option being used to enable
> threads support.
>
> I see Pegasus/Common has thread pool implementation, which is not always
> being used by the applications consuming OenPegasus SDK.
> Let me know if I am wrong somewhere.
>
> Thank You,
> Pranav
>
> On 6 April 2012 16:22, Devchandra Leishangthem <[email protected]>wrote:
>
> Is there any specifi reason why you wanted to build uni-threaded?
> Warm Regards
> D>L> Meetei
> IBM India System and Technology Lab
> EGL -D,Bangalore, India
>
>
>
> From:   Pranav S <[email protected]>
> To:     [email protected],
> Date:   04/06/2012 04:06 PM
> Subject:        How to build OpenPegasus SDK as single threaded?
>
>
>
> Hello,
>
> I am trying to explore OpenPegasus SDK and its applications. Currently the
> SDK uses multi threading and links to pthreads library, hence it gets built
> as a multithreaded. I would like to know is it possible to build the
> library as single threaded? Do we have provision for that in the Makefiles.
> I tried exploring but did not find anything which tells that it is possible
> to build the library as single threaded one. Because linking a single
> threaded library to a multithreaded library can lead to undefined
> behaviour.
>
> --
> Thanks,
> Pranav
>
>
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> --
> Thanks,
> Pranav
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> --
> Thanks,
> Pranav
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> --
> Thanks,
> Pranav
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> --
> Thanks,
> Pranav
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> --
> Thanks,
> Pranav
>
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>
> --
> Thanks,
> Pranav
>
>
>
>


-- 
Thanks,
Pranav