Re: Problem setting buffer size for gfortran ( v 11.2)

__ From: Thomas Koenig Sent: Saturday, February 26, 2022 10:20:25 AM To: Bertini, Denis Dr.; Harald Anlauf Cc: Tobias Burnus; fortran@gcc.gnu.org Subject: Re: Problem setting buffer size for gfortran ( v 11.2) On 25.02.22 21:53, Bertini, Denis Dr. via Fortran wrote: >

Re: Problem setting buffer size for gfortran ( v 11.2)

On 25.02.22 21:53, Bertini, Denis Dr. via Fortran wrote: It seems that the value set in the foreseen environment variable is just ignored. And always a buffer size of 8kiB is used, which is the default values for formatted I/O harcoded in libgfortran. The only way to change this value is editing

Re: Problem setting buffer size for gfortran ( v 11.2)

the libgfortran. Best. Denis From: Harald Anlauf Sent: Friday, February 25, 2022 9:44:53 PM To: Bertini, Denis Dr. Cc: Tobias Burnus; fortran@gcc.gnu.org Subject: Re: Problem setting buffer size for gfortran ( v 11.2) Hi Denis, > exp

Re: Problem setting buffer size for gfortran ( v 11.2)

Hi Denis, export GFORTRAN_UNFORMATTED_BUFFER_SIZE=1 export GFORTRAN_FORMATTED_BUFFER_SIZE=1 export GFORTRAN_UNBUFFERED_ALL=n From the output log indeed i got the correct env. variable as i set: GFORTRAN_FORMATTED_BUFFER_SIZE=1 But from strace output i got always write(3

Re: Re: Problem setting buffer size for gfortran ( v 11.2)

2@"..., 8192) = 8192 write(3, "\0\0\0`ff\22@\0\0\0\340\314\314\22@\0\0\0@33\23@\0\0\0\240\231\231\23@"..., 8192) = 8192 write(3, "\0\0\0\0\0\0\24@\0\0\0`ff\24@\0\0\0\340\314\314\24@\0\0\0@33\25@"..., 8192) = 8192 ..... >>>>>>>>>>>>>>>>>> Showing the

Re: Problem setting buffer size for gfortran ( v 11.2)

run. Are the variables set correct ? Best, Denis From: Tobias Burnus Sent: Thursday, February 24, 2022 9:20:26 AM To: Bertini, Denis Dr.; Harald Anlauf Cc: fortran@gcc.gnu.org Subject: Re: Problem setting buffer size for gfortran ( v 11.2) Hi Denis, On 24.02.22

Re: Problem setting buffer size for gfortran ( v 11.2)

Hi Denis, On 24.02.22 09:15, Bertini, Denis Dr. via Fortran wrote: I can try that but on our cluster we are bound to use srun (slurm). Do you know how to use the same functionality with srun to set the environment variables. I didn't – but the manual did: srun --export=... See: https://slu

Re: Problem setting buffer size for gfortran ( v 11.2)

, Denis Dr.; Harald Anlauf Cc: fortran@gcc.gnu.org Subject: Re: Problem setting buffer size for gfortran ( v 11.2) Hi, On 24.02.22 08:57, Bertini, Denis Dr. via Fortran wrote: > Additonnaly i ran interactively my test program without slurm on with just > one MPI process on I think you eith

Re: Problem setting buffer size for gfortran ( v 11.2)

Hi, On 24.02.22 08:57, Bertini, Denis Dr. via Fortran wrote: Additonnaly i ran interactively my test program without slurm on with just one MPI process on I think you either use Open MPI or MPICH. Can you try setting the environment variable when invoking MPI by adding the -x or -env (-envli

Re: Problem setting buffer size for gfortran ( v 11.2)

: Wednesday, February 23, 2022 10:38:20 PM To: Bertini, Denis Dr. Cc: fortran@gcc.gnu.org Subject: Re: Problem setting buffer size for gfortran ( v 11.2) Hi Denis, if editing of unix.c works: is it possible that you either misspelled the name of the environment variable, forgot to export it, or if you are

Re: Problem setting buffer size for gfortran ( v 11.2)

um 22:23 Uhr Von: "Bertini, Denis Dr." An: "Harald Anlauf" Cc: "fortran@gcc.gnu.org" Betreff: Re: Problem setting buffer size for gfortran ( v 11.2) Hi Harald, I ran also the same with gfortran v11.2. together with singularity and did not work as well. Then i chan

Re: Problem setting buffer size for gfortran ( v 11.2)

singularity container? Best Denis From: Harald Anlauf Sent: Wednesday, February 23, 2022 10:18:17 PM To: Bertini, Denis Dr. Cc: fortran@gcc.gnu.org Subject: Re: Problem setting buffer size for gfortran ( v 11.2) Hi Denis, if I'm reading the strace o

Re: Problem setting buffer size for gfortran ( v 11.2)

behavior. (E.g. the HDF5 library is known to hit bugs in our Lustre.) Cheers, Harald Best Denis From: Harald Anlauf Sent: Wednesday, February 23, 2022 7:26 PM To: Bertini, Denis Dr.; fortran@gcc.gnu.org Subject: Re: Problem setting buffer size for gfortran ( v 1

Re: Problem setting buffer size for gfortran ( v 11.2)

rg Subject: Re: Problem setting buffer size for gfortran ( v 11.2) Hi Denis, Am 23.02.22 um 17:10 schrieb Bertini, Denis Dr. via Fortran: > Hi > Investigating some sporadical performance drop when using Fortran IO on our > Lustre > shared file system, we realized that the buffer size

Re: Problem setting buffer size for gfortran ( v 11.2)

Hi Denis, Am 23.02.22 um 17:10 schrieb Bertini, Denis Dr. via Fortran: Hi Investigating some sporadical performance drop when using Fortran IO on our Lustre shared file system, we realized that the buffer size used as default by the gnu fortran compiler is 8 kiB only. We wanted to change this

Problem setting buffer size for gfortran ( v 11.2)

Hi Investigating some sporadical performance drop when using Fortran IO on our Lustre shared file system, we realized that the buffer size used as default by the gnu fortran compiler is 8 kiB only. We wanted to change this default and according to the documentation, one has just to set the envir