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Re: limit

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Paul Edwards wrote:
> Next issue.
>
> I was surprised to be running out of memory
> when doing this:
>
> [P:\devel\gcc\gcc\xxx]type temp.cmd
> \dos\pdas --oformat coff -o c-common.o c-common.s
> [P:\devel\gcc\gcc\xxx]
>
>
> When I added the "requesting" debug I got this:
>
> requesting 32 bytes, total 636279, attempts 7394
> requesting 44 bytes, total 636323, attempts 7395
> requesting 44 bytes, total 636367, attempts 7396
> stdlib reports alloc failure
> \dos\pdas: error: memory full (malloc)
>
> But without the debug, I didn't get that "alloc failure"
> message. Instead I got an OS/2 popup saying I was short
> of unspecified resources.
>
> Now I thought there was a limit of 512 MB by default,
> but there is an actual OBJ_TILE flag to DosAllocMem
> to restrict it to that it seems.
>
> And a different flag for OBJ_ANY.
>
> Which means the default is what?

I'd think 512M. It was all that was available until Warp v4.5 (earlier 
with Warp server)

>
> Now I know it is not ideal to call DosAllocMem for
> every memory allocation requested and I should use
> a heap manager (I actually have one (memmgr), but I
> prefer not to use it, for simplicity).
>
> Even with 4k granularity, there are less than 8000
> requests, so that's 32 MB additional overhead, on
> top of ... less than 1 MB.

Warp 4 (Warp 3?) has 64k granularity, older had 4k

>
> So I suspect there is a limit of around 8000 separate
> requests. I'm guessing this is to keep within the
> limit of 80386 selectors so that someone may
> request this memory to be converted to 16:16

There does seem to be other limits, perhaps just in the WPS.

>
> Anyway, adding OBJ_ANY allowed the memory requests
> to continue:
>
> requesting 6152 bytes, total 849766, attempts 10683
> requesting 40 bytes, total 849806, attempts 10684
> requesting 40 bytes, total 849846, attempts 10685
> requesting 40 bytes, total 849886, attempts 10686
>
>
> And I didn't experience any issues with DosWrite
> etc either.
>
> From memory it is DosOpen that has the issue, not
> DosWrite. And so long as my executable is loaded
> below 512 MiB - which is under OS/2 control - I
> shouldn't have any issue with parameters to
> DosOpen being above the 512 MiB line.
>
> Well - the second parameter could potentially be
> in high memory, but that would be an unlikely,
> but I guess not impossible, thing to be internally
> mapped to 16:16.
>
> rc = DosOpen((PSZ)fnm,
>              &myfile->hfile,
>              &action,
>              newsize,
>              fileAttr,
>              openAction,
>              openMode,
>              (ULONG)0);
>
> But for now, it works, and with this problem fixed
> or circumvented, I should be up and running soon.

mem /v at the command line will show aprox free mem.
If you really want to explore memory allocations, and other interesting 
system level stuff, install Theseus, 
http://hobbesarchive.com/Home/Download?path=/Hobbes/pub/os2/util/memory/Theseus_4-001.exe 
or ftp://service.boulder.ibm.com/ps/products/os2/fixes/v4.5warp/theseus4
Dave

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limit Paul Edwards <mutazilah@gmail.com> - 2024-03-14 01:56 +0800
  Re: limit Dave Yeo <dave.r.yeo@gmail.com> - 2024-03-13 15:13 -0700
    Re: limit Paul Edwards <mutazilah@gmail.com> - 2024-03-14 09:07 +0800
      Re: limit Paul Edwards <mutazilah@gmail.com> - 2024-03-14 11:53 +0800
        Re: limit "Andi B." <andi.b@gmx.net> - 2024-03-14 10:53 +0100
      Re: limit Dave Yeo <dave.r.yeo@gmail.com> - 2024-03-13 21:06 -0700

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