[GRASS-user] r.mapcalc multiprocess

[Blumentrath, Stefan]

Hi Lorenzo,


I guess you would have to set the WORKERS environment variable to the number of concurrent processes you want to have, e.g.

export WORKERS=4

But again, I do not think that this is recommended! Developers would be able to tell you more...


Cheers

Stefan



________________________________
Von: Lorenzo Bottaccioli <lorenzo.bottaccioli at gmail.com>
Gesendet: Freitag, 11. März 2016 12:16
An: Blumentrath, Stefan
Cc: GRASS user list
Betreff: Re: [GRASS-user] r.mapcalc multiprocess

Hi Stefan,

I have just updated my grass-gis version to 7.0.3, berfore I was using 7.0.0 version and mapcalc was running in multitheard mode and was much faster. My question is how can i make it run again in multitheading?

Regards,

Lorenzo

2016-03-10 22:39 GMT+01:00 Blumentrath, Stefan <Stefan.Blumentrath at nina.no<mailto:Stefan.Blumentrath at nina.no>>:
Hi,

As far as I know it is not exactly recommended to compile with pthread, and if I recall the latest discussion correctly, the number of default workers was deliberately set to 1 due to issues with multithreaded r.mapcalc.

Don`t know which was the latest discussion on this topic, but it has been discussed / explained in detail on the developer list, e.g.:
https://lists.osgeo.org/pipermail/grass-dev/2012-June/058749.html
https://lists.osgeo.org/pipermail/grass-dev/2008-November/041047.html

Hope that helps a bit.

Kind regards,
Stefan

From: grass-user [mailto:grass-user-bounces at lists.osgeo.org<mailto:grass-user-bounces at lists.osgeo.org>] On Behalf Of Lorenzo Bottaccioli
Sent: 10. mars 2016 17:14
To: GRASS user list <grass-user at lists.osgeo.org<mailto:grass-user at lists.osgeo.org>>
Subject: [GRASS-user] r.mapcalc multiprocess

Hi every one,

I have just compiled grass with phtreds but when I run r.mapcalc it runs in only with one theard. How ca I fix this? Is it possible to check if is correclty compiled with phtreads?

Tnx

Lorenzo

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/grass-user/attachments/20160311/099b63a1/attachment.html>