Great News Jan! I'm out of office for the next 2 days, as soon i can connect i will try it with pleasure.
TIA! Rogério Soares On Wed, Dec 14, 2011 at 10:20 AM, Jan Glauber <[email protected]>wrote: > On Fri, 2011-12-02 at 14:05 -0600, David Boyes wrote: > > > It's just mmap'ing the whole disk into the process's address space for > the > > > programmers sake. > > > > BAD idea (in the sense of 'broken as designed'). You're taxing the > virtual memory system in a shared-resource environment, which hurts the > entire environment for a little convenience in programming. > > > > > If that turns out to be a problem we could theoretically go back to > > > pread/pwrite. But I'm not sure how many users have such large CMS > disks? > > > > Please do. Doesn't matter if it's an edge case, it shouldn't do this. > > Since there seems to be collective disapproval of the requirement to > touch the memory settings for large disks I'm looking into changing > that... > > I can easily replace the mmap-memcpy with pread/pwrite. Unfortunately I > see huge performance drops if I do so. Currently I'm looking why the > system call variant costs so much more than mmap. > > Jan > > > ---------------------------------------------------------------------- > > For LINUX-390 subscribe / signoff / archive access instructions, > > send email to [email protected] with the message: INFO LINUX-390 > or visit > > http://www.marist.edu/htbin/wlvindex?LINUX-390 > > ---------------------------------------------------------------------- > > For more information on Linux on System z, visit > > http://wiki.linuxvm.org/ > > > > ---------------------------------------------------------------------- > For LINUX-390 subscribe / signoff / archive access instructions, > send email to [email protected] with the message: INFO LINUX-390 or > visit > http://www.marist.edu/htbin/wlvindex?LINUX-390 > ---------------------------------------------------------------------- > For more information on Linux on System z, visit > http://wiki.linuxvm.org/ > ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390 ---------------------------------------------------------------------- For more information on Linux on System z, visit http://wiki.linuxvm.org/
