[GRASS-user] r.mapcalc multiprocess

GRASS GRASS user
1

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

2

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

···

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

3

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@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@lists.osgeo.org] On Behalf Of Lorenzo Bottaccioli
Sent: 10. mars 2016 17:14
To: GRASS user list <grass-user@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

4

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@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@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@lists.osgeo.org] On Behalf Of Lorenzo Bottaccioli
Sent: 10. mars 2016 17:14
To: GRASS user list <grass-user@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