This is the mail archive of the cygwin mailing list for the Cygwin project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: interpretation of %CPU in 'procps' output for multi-cpu & hyperthreading


Tom Rodman wrote:
I would guess gzip must run on exactly 1 cpu, at any given time.
If so, then at most, gzip could use 1/8 of the total
CPU resources or 12.5%, as reported by windows task manager,
right?  So procps is reporting the percent of the current virtual CPU,
that gzip is using, right?

Notice that 'pslist' (from SysInternals) shows gzip, using
9%; 9/12.5 * 100 = 72% of 1 virtual CPU.

Is there a way to prove that a given process with more than 1 thread,
is still restricted to just one CPU?

Unless you have manually set affinity, why would this be true? More likely, only one thread is actually doing anything.


--
Matthew
If a signature
is not read by anyone,
does it make a sound?


-- Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple Problem reports: http://cygwin.com/problems.html Documentation: http://cygwin.com/docs.html FAQ: http://cygwin.com/faq/


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]