I am converting a Carbon app to Cocoa (where I'm a newbie). The Carbon app
was multithreaded and heavily dependent on cblas and clapack. It worked
well and was fully twice as fast with 2 CPUs as with 1. However, the code
was becoming increasingly obsolete.
I now have a Cocoa [ObjectiveC++] vers
FWIW you can't always be sure that NSOperationQueue will be using a
thread per operation. The number of active operations (I explicitly
don't say "threads" here) depends on system contention. Are your
operations dependent on each other or using shared resources? Are you
setting -[NSOperat
I don't have very much by way of help for you because honestly I
don't think there's enough information here for more than
generalities, but ..
1) With 1 CPU (NSOperation not used), I get 50% of CPU-time devoted to
auto_collection_thread which I presume means Garbage Collection. Is
th
On Aug 18, 2009, at 10:36 AM, Jonathan Dann wrote:
You may even find that NSOperationQueue/NSOperation allows you to
split up your calculations into smaller chunks than 1 per CPU (or
effective cores).
In support (I think) of this point, have you seen this article,
Michael?
http://www.
On Aug 18, 2009, at 7:25 AM, McLaughlin, Michael P. wrote:
1) With 1 CPU (NSOperation not used), I get 50% of CPU-time devoted to
auto_collection_thread which I presume means Garbage Collection. Is
this
normal? It seems excessive.
It sounds like your algorithm is doing a tremendous amount
On Aug 18, 2009, at 10:19 AM, McLaughlin, Michael P. wrote:
On 8/18/09 11:34 AM, "Bill Bumgarner" wrote:
On Aug 18, 2009, at 7:25 AM, McLaughlin, Michael P. wrote:
1) With 1 CPU (NSOperation not used), I get 50% of CPU-time
devoted to
auto_collection_thread which I presume means Garbage C
On 8/18/09 1:46 PM, "Bill Bumgarner" wrote:
> On Aug 18, 2009, at 10:19 AM, McLaughlin, Michael P. wrote:
>
>> On 8/18/09 11:34 AM, "Bill Bumgarner" wrote:
>>
>>> On Aug 18, 2009, at 7:25 AM, McLaughlin, Michael P. wrote:
>>>
1) With 1 CPU (NSOperation not used), I get 50% of CPU-time
>>
On Aug 18, 2009, at 7:25 AM, McLaughlin, Michael P. wrote:
1) With 1 CPU (NSOperation not used), I get 50% of CPU-time devoted to
auto_collection_thread which I presume means Garbage Collection. Is
this
normal? It seems excessive.
2) With 2 CPUs, I get 26% of CPU-time for auto_collection_th
