Re: VSIZE, apps without AppKit
Re: VSIZE, apps without AppKit
- Subject: Re: VSIZE, apps without AppKit
- From: Sherm Pendley <email@hidden>
- Date: Fri, 5 Apr 2002 18:31:35 -0500
On Friday, April 5, 2002, at 05:01 PM, Angela Brett wrote:
I wrote a Foundation Tool, which I have now put into an Application
solely so that it can be added as a Login Iten. I've removed all
remnants of the AppKit from the project, since I don't need it and as
soon as I use anything from the AppKit the VSIZE (as mentioned in top)
goes up to about 30 or 50MB. I don't know ir that's really a bad thing,
but it seems quite wasteful for something which is meant to be running
all the time, and which doesn't actually need anything from the AppKit.
That's my first question... if I do use the AppKit in this program, how
much difference does that really make? Will that extra size slow down
the system at all?
It shouldn't make any noticable difference. VSIZE is the total virtual
address space accessible to your application, including that shared by
other processes, such as that used by AppKit and other dynamic libraries
and frameworks. RSIZE is the total resident memory; that is, the amount
of real, physical RAM used, including that shared by other processes.
The difference between VSIZE and RSIZE represents the amount of space
that has been mapped into your application's address space, but not
loaded. Memory-mapped file i/o is commonly used for this; that is, code
segments are mapped to data that resides on disk, but they're not
actually loaded until the memory addresses in question are actually
used. I say "commonly" because I haven't investigated how Darwin
implements this concept; this technique is used by both Solaris and
Linux. The concept is similar, however, regardless of the implementation
details.
RSHRD is the amount of resident memory that's currently shared with
other processes. RPRVT is the amount of resident memory that's unique to
your application.
A longer explanation can be found in "man top".
sherm--
_______________________________________________
cocoa-dev mailing list | email@hidden
Help/Unsubscribe/Archives:
http://www.lists.apple.com/mailman/listinfo/cocoa-dev
Do not post admin requests to the list. They will be ignored.