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Re^2: WMI query with Threads

by BrowserUk (Pope)
on Feb 13, 2013 at 20:58 UTC ( #1018633=note: print w/ replies, xml ) Need Help??


in reply to Re: WMI query with Threads
in thread WMI query with Threads

The only thing that multi-threading can realistically do is to overlap computation with I/O, and, to a certain but limited extent, to allow multiple I/O requests to be serviced in parallel.

That statement is garbage. There is nothing "limited" about the possibility of servicing multiple IO requests concurrently. And what about the possibility of performing concurrent computation on multiple cpus?

Why do you insist of posting on subjects that you obviously have no useful knowledge of?

Could it be that you know that even your garbage replies will often garner you a few upvotes?


With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.


Comment on Re^2: WMI query with Threads
Re^3: WMI query with Threads
by sundialsvc4 (Monsignor) on Feb 13, 2013 at 23:30 UTC

    I don’t make replies or comments that are intended to be “garbage,” nor would I for any reasoning as puerile as “upvotes” even if such a practice would garner any .. which I doubt.   Puh-leeuze.

    Multi-threading this particular program is of doubtful merit, and I simply made the comment in the context of what I see this program doing.   Yes, it will be able to overlap doing multiple network pings at one time.   That’s the only payoff that I see for what has suddenly become a very complicated design.   There is no computation to be done here; all of the threads are going to gang-up on the SQL server, and their printed outputs are going to pop out very piecemeal.   These threads have no real opportunity to “run free.”   They only ping in parallel ... that’s it.

    Hence, the warning-bells going off, hence the suggestion to “be sure” that a payoff, commensurate with the time already spent and the difficulty already encountered, actually exists in this case and for this program.   I think that this application is a very poor candidate for a multi-threaded implementation.

      You make statements -- that you must just pluck out of your own imagination -- that simply don't make sense.

      1. Multi-threading this particular program is of doubtful merit, ... Yes, it will be able to overlap doing multiple network pings at one time. Thatís the only payoff ...

        On a 100Mb/s network, average icmp ping times are around 0.2 milliseconds. The OP is using a 10 second timeout for his pings. In the same time that one thread spends waiting for an unresponsive server to time out; another thread can have successfully pinged 10/0.0002 = 50,000 machines!

        And if the OP is on a 1Gb/s or a 10Gb/s or 40Gb/s network ...

        Payoff enough I think. But there's more ...

      2. There is no computation to be done here; all of the threads are going to gang-up on the SQL server,

        Firstly, WMIC isn't an SQL server. It responds to SQL queries, but there is no separate server involved to "gang-up on".

        WMIC is an OS internal -- memory based -- DB; and the code that performs the queries runs in the thread that invokes the query!

        In other words, all the computation done to fulfill the query, is done by the calling thread!

      You are helping no one with answers that are this far off base.


      With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
      Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
      "Science is about questioning the status quo. Questioning authority".
      In the absence of evidence, opinion is indistinguishable from prejudice.

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