Santiago Vila <> writes:

> On Sun, 2 Oct 2016, Camm Maguire wrote:
>> Greetings!  I just wanted to keep you abreast of the latest upload.
>> I've put in an improvement which I hope will allow better use of the
>> ram available without running into the fork/exec faults we had seen in
>> some configurations.  This does not address the question of 'how much
>> memory should we attempt to make use of', but you may find this upload
>> more robust nonetheless.  GCL_MEM_MULTIPLE defaults back to 1.0 from
>> 0.85 without apparent issue.
>> Feedback appreciated.
> Hello.
> I finally tested maxima_5.38.1-2 today.


> On a machine with 6GB RAM and 4 GB swap, memory usage was about
> 7500 MB (1500 MB more than the available RAM).
> On a machine with 3GB RAM and 4 GB swap, memory usage was about
> 3700 MB (700 MB more than the available RAM).
> I'm still measuring memory usage with Committed_AS, by taking note of
> its value during the build and substracting the value before the build
> starts.
> In your previous email, you suggest that I don't use Committed_AS
> to measure memory usage, but something else.

Because the linux docs say this is an anticipated worst case guess, not
the amount of memory in use.

> I'm not sure what else I could use instead which is better than
> Committed_AS, and I fear that the more memory I have available, the
> more memory would maxima use as well, just as it happens with
> Committed_AS, so are you sure that using something else other
> than Committed_AS would really fix my problem?

If you use the variables I output in my post, I think you will find that
the build does not swap.

> Do you have a suggestion about which other parameter in /proc/meminfo
> would be more suitable than Committed_AS?

These were the variables I output in my sample build.

> Maybe this Committed_AS value being higher than the available RAM is
> "normal and expected", but the way I see it, it seems part of a
> general problem called "overcommit".

Indeed, all unices nowadays do this.

> The question would be: How much overcommit should we reasonably expect
> from a package when it's being built?

I think it is reasonable that a program make use of the available ram as
long as it stays out of swap.

Take care,

> [ I still have to read your previous email in detail, this is just a
>   first reply to tell my experience with maxima_5.38.1-2 ]
> Thanks.

Camm Maguire                              
"The earth is but one country, and mankind its citizens."  --  Baha'u'llah

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