Hello,
I installed yambo version 3.2.1 revision 448 under linux with ext3 file system.
It works fine and yambo passed all tests.
However, the ext3 file system has a limit on the number of sub-directories.
The limit is about 32000 sub-directories. When I perform the BSE calculation for GaN with
hexagonal cell with many k-point, this limit can be exceeded.
My questions are following:
1. Is it possible to avoid creation of so many sub-directiories in SAVE directory?
2. What kind of file system do you use for yambo?
3. What do you suggest?
Best regards,
Zbigniew Romanowski
Institute of High Pressure Physics
Polish Academy of Sciences
Warsaw, Poland
Too many sub-directories
Moderators: Davide Sangalli, andrea.ferretti, myrta gruning, andrea marini, Daniele Varsano, Conor Hogan, Nicola Spallanzani
- andrea marini
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Re: Too many sub-directories
Hi,
the number of blocks the BS Hamiltonian is dived decides the number of subfolders. The number of blocks is given by the number of k-points you have in the whole BZ. How many k-points do you have ?
To avoid the fragmentation you can edit yourself the src/io/ioBS.F routine, and in particular, the lines
If dbs_fragment=.TRUE. then the blocks are spread in subdirectories to speed up the I/O. You can force by hand the logical to be false. HOWEVER if your matrix is huge the I/O in the solver will be really slowed down.
Another solution is to replace subfolders with files. In this case you need to do a little bit more of coding. PLease first try the other option and let me know.
Andrea
the number of blocks the BS Hamiltonian is dived decides the number of subfolders. The number of blocks is given by the number of k-points you have in the whole BZ. How many k-points do you have ?
To avoid the fragmentation you can edit yourself the src/io/ioBS.F routine, and in particular, the lines
Code: Select all
if (write_is_on(ID)) then
db_is_large=BS_K_dim>6000
if (BS_K_coupling) db_is_large=BS_K_dim>3000
if (db_is_large) then
dbs_fragment=.true.
io_fragmented(ID)=.true.
endif
endif
Another solution is to replace subfolders with files. In this case you need to do a little bit more of coding. PLease first try the other option and let me know.
Andrea
Andrea MARINI
Istituto di Struttura della Materia, CNR, (Italy)
Istituto di Struttura della Materia, CNR, (Italy)
- andrea marini
- Posts: 325
- Joined: Mon Mar 16, 2009 4:27 pm
- Contact:
Re: Too many sub-directories
If you can solve your problem by using files instead of folders for the fragments of the BS Hamiltonian let me know as I already wrote a small patch to do this. I can post it if you need.andrea marini wrote: Another solution is to replace subfolders with files. In this case you need to do a little bit more of coding. PLease first try the other option and let me know.
Andrea MARINI
Istituto di Struttura della Materia, CNR, (Italy)
Istituto di Struttura della Materia, CNR, (Italy)
-
- Posts: 3
- Joined: Fri Jun 26, 2009 10:34 am
Re: Too many sub-directories
Dear Andrea,
I think we have exactly the same problem (ext3 file system) with the maximum number of sub-directories.
In the last post you say you have a patch to replace directories with files. Can you post it????
ciao,
Silvana
I think we have exactly the same problem (ext3 file system) with the maximum number of sub-directories.
In the last post you say you have a patch to replace directories with files. Can you post it????
ciao,
Silvana
- andrea marini
- Posts: 325
- Joined: Mon Mar 16, 2009 4:27 pm
- Contact:
Re: Too many sub-directories
Dear Silvana,
the patch has been included in one of the latest revisions in the SVN repository. Can you try to download it ? Instructions are given in the download page.
Ciao
Andrea
the patch has been included in one of the latest revisions in the SVN repository. Can you try to download it ? Instructions are given in the download page.
Ciao
Andrea
Andrea MARINI
Istituto di Struttura della Materia, CNR, (Italy)
Istituto di Struttura della Materia, CNR, (Italy)