* stefan parvu ([EMAIL PROTECTED]) [000306 09:19]:
> I have not so much experience using POSIX threads, but we had in
> university a project and for I/O to use threads is not so good method.
> You slow down the process.
>
> Some comments? Isn't so?
In my experience, threads are the perfect way to speed up an I/O bound
application. While one thread is blocked in iowait, others can be
performing operations that do not contend for the same resource
(calculation, I/O on some other resource like a socket, etc.)
This is of course implementation dependant; if you are using a user-land
thread package like MIT pthreads, the kernel sees the entire process as one
schedulable entity, so if one thread blocks on IO, all threads block. If
you are using a kernel-thread or hybrid implementation, the system scheduler
allows the other threads to run as described above.
FreeBSD's threading implementation in libc_r is (AFAIK) a hybrid model, and
from personal experience I have found threaded applications under FreeBSD to
be much easier to code for performance than their single-threaded
counterparts.
--
j.
James FitzGibbon [EMAIL PROTECTED]
Targetnet.com Inc. Voice/Fax +1 416 306-0466/0452
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