Re: Application priority

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Hi mate

This is the result of windows being 'fair' to all threads.

Indeed, it is - this is the main idea behind priority boosts. However,
it applies only to threads in the dynamic range - if thread priority is
in the real-time range, it will always run at its base priority (
priority boost cannot take thread from dynamic range to real-time one)

Read all about
it in MSDN by looking up SetThreadPriority.

In fact, "Windows Internals" provides much more detailed explanation of
the concept, compared to that of MSDN ........


Anton Bassov

m wrote:
This is the result of windows being 'fair' to all threads. Read all about
it in MSDN by looking up SetThreadPriority.

"anton bassov" <soviet_bloke@xxxxxxxxxxx> wrote in message
news:1157486835.355608.256230@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Hi mate

How come that the rountrip times increase when Cpukiller runs at normal
priority even though my processes runs above normal priority?

You should clearly realize that, as long as thread priority falls into
the dynamic range,
priority in itself is quite relative thing - the system may increase
priority of a thread that
has not been active for quite a while. Apparently, when you have
specifed Normal priority, the target thread still has a chance to run
from time to time, due to priority boost
that gets applied by the system behind the scenes. Therefore, you get a
delay.

Anton Bassov

ixrob wrote:
Hi

I have a service running at high prio. My test app running above normal
priority communicates with a remote device via the service using tcp. The
request/response time is less than 20 ms. They take less tan 10% of the
cpu.

When I load the cpu to 100% with Cpukiller3 (an application which kills
cpu
time) running at Normal prio the request/response time increase to more
than
200ms. If I run Cpukiller3 Below Normal priority and load the cpu 100% I
get
my 20ms again (?).

How come that the rountrip times increase when Cpukiller runs at normal
priority even though my processes runs above normal priority?


.

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