Re: [HACKERS] fstat vs. lseek

2011-10-28 Thread Andres Freund
Hi All, The lseek patches just got included in Linus tree. Andres -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers

Re: [HACKERS] fstat vs. lseek

2011-10-28 Thread Robert Haas
On Fri, Oct 28, 2011 at 3:33 PM, Andres Freund and...@anarazel.de wrote: The lseek patches just got included in Linus tree. Excellent, thanks for the update! http://git.kernel.org/?p=linux/kernel/git/torvalds/linux.git;a=commit;h=ef3d0fd27e90f67e35da516dafc1482c82939a60 So I guess this will be

Re: [HACKERS] fstat vs. lseek

2011-10-28 Thread Andres Freund
Hi, On Friday, October 28, 2011 09:40:51 PM Robert Haas wrote: On Fri, Oct 28, 2011 at 3:33 PM, Andres Freund and...@anarazel.de wrote: The lseek patches just got included in Linus tree. Excellent, thanks for the update!

Re: [HACKERS] fstat vs. lseek

2011-09-16 Thread Andrea Suisani
hi On 08/08/2011 07:50 PM, Robert Haas wrote: On Mon, Aug 8, 2011 at 1:31 PM, Andres Freundand...@anarazel.de wrote: If its ok I will write a mail to lkml referencing this thread and your numbers inline (with attribution obviously). That would be great. Please go ahead. I've just

Re: [HACKERS] fstat vs. lseek

2011-09-16 Thread Andres Freund
On Friday 16 Sep 2011 15:19:07 Andrea Suisani wrote: hi On 08/08/2011 07:50 PM, Robert Haas wrote: On Mon, Aug 8, 2011 at 1:31 PM, Andres Freundand...@anarazel.de wrote: If its ok I will write a mail to lkml referencing this thread and your numbers inline (with attribution obviously).

[HACKERS] fstat vs. lseek

2011-08-08 Thread Robert Haas
In response to my blog post on lseek contention, someone posted a comment wherein they proposed using fstat() rather than lseek() to get file sizes. http://rhaas.blogspot.com/2011/08/linux-and-glibc-scalability.html I tried that on a RHEL 6.1 machine with 64-cores running

Re: [HACKERS] fstat vs. lseek

2011-08-08 Thread Tom Lane
Robert Haas robertmh...@gmail.com writes: In response to my blog post on lseek contention, someone posted a comment wherein they proposed using fstat() rather than lseek() to get file sizes. Patch and test results are attached. Test runs are 5-minute runs with scale factor 100 and

Re: [HACKERS] fstat vs. lseek

2011-08-08 Thread Andres Freund
On Monday, August 08, 2011 10:30:38 Robert Haas wrote: In response to my blog post on lseek contention, someone posted a comment wherein they proposed using fstat() rather than lseek() to get file sizes. Thoughts? I don't think its a good idea to replace lseek with fstat in the long run. The

Re: [HACKERS] fstat vs. lseek

2011-08-08 Thread Robert Haas
On Mon, Aug 8, 2011 at 10:45 AM, Tom Lane t...@sss.pgh.pa.us wrote: I'm a bit concerned by the fact that you've only tested this on one operating system, and thus the performance characteristics could be quite different elsewhere.  The comment in mdextend also points out a way in which this

Re: [HACKERS] fstat vs. lseek

2011-08-08 Thread Andres Freund
On Monday, August 08, 2011 11:33:29 Robert Haas wrote: On Mon, Aug 8, 2011 at 10:49 AM, Andres Freund and...@anarazel.de wrote: I don't think its a good idea to replace lseek with fstat in the long run. The likelihood that the lockless generic_file_llseek will get included seems rather

Re: [HACKERS] fstat vs. lseek

2011-08-08 Thread Robert Haas
On Mon, Aug 8, 2011 at 1:10 PM, Andres Freund and...@anarazel.de wrote: There doesn't seem to have been any activity to inlude it in 3.1. The merge window for 3.1 just ended. The next one will open for about a week after the release. Its also not yet included in linux-next which is a preview

Re: [HACKERS] fstat vs. lseek

2011-08-08 Thread Tom Lane
Robert Haas robertmh...@gmail.com writes: Not really. I do have root access to a 64-core box at the moment, and I could probably get permission to reboot it, but if it didn't come back on-line that would be awkward. Red Hat has some test hardware that I can use (... pokes around ...) Hmm,

Re: [HACKERS] fstat vs. lseek

2011-08-08 Thread Andres Freund
On Monday, August 08, 2011 13:19:13 Robert Haas wrote: On Mon, Aug 8, 2011 at 1:10 PM, Andres Freund and...@anarazel.de wrote: There doesn't seem to have been any activity to inlude it in 3.1. The merge window for 3.1 just ended. The next one will open for about a week after the release.

Re: [HACKERS] fstat vs. lseek

2011-08-08 Thread Robert Haas
On Mon, Aug 8, 2011 at 1:31 PM, Andres Freund and...@anarazel.de wrote: If its ok I will write a mail to lkml referencing this thread and your numbers inline (with attribution obviously). That would be great. Please go ahead. I don't think it will be that hard to convince them. But I