Opened 12 years ago
Closed 11 years ago
#1121 closed Bug (fixed)
OBC in parallel
Reported by: | julienjouanno | Owned by: | epico |
---|---|---|---|
Priority: | low | Milestone: | |
Component: | OCE | Version: | trunk |
Severity: | Keywords: | ||
Cc: | epico |
Description
It seems there is a problem with OBC when running in parallel.
It works fine when using a few procs (1,2,4). The solver.stat are then strictly equal. When using 8 procs it depends on the distribution (2*4 works but not 4*2). When using a higher number of procs it does not work anymore and fail with mpi errors at the first or second time step.
This problem seems to be solved (I ran one year !) when replacing the current subroutine mppobc with mppobc from nemo_3.4.
Commit History (2)
Changeset | Author | Time | ChangeLog |
---|---|---|---|
4047 | epico | 2013-10-01T06:59:38+02:00 | bug fix in mppobc. ticket #1121 |
4017 | epico | 2013-09-09T15:15:27+02:00 | Bug fixed in mppobc routine. see Ticket #1121 |
Change History (2)
comment:1 in reply to: ↑ description ; follow-up: ↓ 2 Changed 12 years ago by epico
- Cc epico added
- Owner changed from NEMO team to epico
- Status changed from new to assigned
comment:2 in reply to: ↑ 1 Changed 11 years ago by epico
- Resolution set to fixed
- Status changed from assigned to closed
The bug concerns the communication pattern among the processes on the boundary in the mppobc routine, namely, it rises up when some of the processes on the boundary do not have any point to send.
The bug has been fixed
The fix has been tested with the NATL025 configuration provided by julien using 64 processes with a run of 6 months and a restartability run with 3mo+3mo
Replying to epico:
Dear Julien
we have tested again the OBC on our configuration with NEMO v3.5 and we did not found any problem up to 32 processes.
Can you provide us with your configuration/settings or more details on the error ?
best regards
Italo Epicoco
Replying to julienjouanno:
It seems there is a problem with OBC when running in parallel.
It works fine when using a few procs (1,2,4). The solver.stat are then strictly equal. When using 8 procs it depends on the distribution (2*4 works but not 4*2). When using a higher number of procs it does not work anymore and fail with mpi errors at the first or second time step.
This problem seems to be solved (I ran one year !) when replacing the current subroutine mppobc with mppobc from nemo_3.4.
Dear Julien
we have tested again the OBC on our configuration with NEMO v3.5 and we did not found any problem up to 32 processes.
Can you provide us with your configuration/settings or more details on the error ?
best regards
Italo Epicoco
Replying to julienjouanno: