Multithreading

[Enrico Maria Giordano]

Antonio,

what do you think about this sample (xHarbour):

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FUNCTION MAIN()    LOCAL hThr := STARTTHREAD( @MyFunc() )    INKEY( 0 )    STOPTHREAD( hThr )    INKEY( 0 )    RETURN NILSTATIC FUNCTION MYFUNC()    WHILE .T.        THREADSLEEP( 1000 )        TONE( 440, 1 )    ENDDO    RETURN NIL

EMG

[Silvio.Falconi]

what I can do with it ?

[Antonio Linares]

Enrico,

It seems what you were looking for

Does it work fine ?

[Enrico Maria Giordano]

Silvio,

what I can do with it ?

I'm experimenting a way to make wait animations smooth even with loops without SysRefresh() inside them.

EMG

[Enrico Maria Giordano]

Antonio,

Enrico,

It seems what you were looking for

Does it work fine ?

It seems so.

EMG

[Enrico Maria Giordano]

I just found that MT EXEs are slower than ST ones.

Any comments?

EMG

[Antonio Linares]

Enrico,

How have you measured it ?

[Enrico Maria Giordano]

Antonio,

Enrico,

How have you measured it ?

With Seconds(). What else?

EMG

[Antonio Linares]

Could you provide a small example of what you tested ? thanks

[Enrico Maria Giordano]

Antonio,

Could you provide a small example of what you tested ? thanks

Something like this:

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FUNCTION MAIN()    LOCAL nSec    LOCAL cVal    USE MYTABLE    nSec = SECONDS()    WHILE !EOF()        cVal = FIELD -> myfield        SKIP    ENDDO    ? "Assign and skip", SECONDS() - nSec    CLOSE    INKEY( 0 )    RETURN NIL

Here I get ST: 31 MT: 41!

EMG

[StefanHaupt]

Enrico,

just to understand, what could be the advantages using MT instead of ST ? What functions could be put in threads ?

Im my understanding a database application is a single thread application with single tasks, e.g. browsing a dbf or searching in a dbf. What can be done, to get simultaneous tasks ?

Stefan

[Enrico Maria Giordano]

Stefan,

Enrico,

just to understand, what could be the advantages using MT instead of ST ? What functions could be put in threads ?

Im my understanding a database application is a single thread application with single tasks, e.g. browsing a dbf or searching in a dbf. What can be done, to get simultaneous tasks ?

Stefan

Don't know. I just need something to get smooth wait animations during loops without SysRefresh() in them.

EMG

[Antonio Linares]

Enrico,

Thanks for your example, what source code had you running on the second thread ?

[Enrico Maria Giordano]

Antonio,

Enrico,

Thanks for your example, what source code had you running on the second thread ?

Nothing. I created no threads. Just link vmmt.lib and cw32mt.lib in.

EMG

[Antonio Linares]

Enrico,

How many records you have on the DBF ?