Date: Wed, 18 Apr 2012 23:41:30 +0200 From: Robert Millan <rmh@freebsd.org> To: freebsd-arch@freebsd.org Subject: Increase DFLDSIZ on amd64? Message-ID: <CAOfDtXMSQ_iT8zQKjrQ-4AxFDtNoNNj-7-=kXGT6RdOMOtyXUA@mail.gmail.com>
next in thread | raw e-mail | index | archive | help
[-- Attachment #1 --] Hi, Is there any reason for DFLDSIZ being so low (128 MiB) on amd64? We've recently had a bunch of trouble in Debian when attempting to run the CMOR testsuite. Its testcases require about ~700 MiB to pass. We also found references recommending higher values for applications like SAP [2] or MySQL [3]. I understand on i386 there's a shortage of virtual memory, but on amd64 there's plenty of it. It seems this is already reflected on the MAXDSIZ setting (32 GiB), but DFLDSIZ is still the same as on i386. Wouldn't 32 GiB be a sound value as the default limit too? Is there any unreasonable cost or security consideration associated with allocating so many pages? Thanks [1] http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=661283 [2] http://www.freebsd.org/doc/handbook/sapr3.html#KERNELTUNING [3] https://dev.mysql.com/doc/refman/5.0/en/freebsd.html -- Robert Millan [-- Attachment #2 --] Index: sys/amd64/include/vmparam.h =================================================================== --- sys/amd64/include/vmparam.h (revision 234389) +++ sys/amd64/include/vmparam.h (working copy) @@ -54,7 +54,7 @@ */ #define MAXTSIZ (128UL*1024*1024) /* max text size */ #ifndef DFLDSIZ -#define DFLDSIZ (128UL*1024*1024) /* initial data size limit */ +#define DFLDSIZ (32768UL*1024*1024) /* initial data size limit */ #endif #ifndef MAXDSIZ #define MAXDSIZ (32768UL*1024*1024) /* max data size */
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?CAOfDtXMSQ_iT8zQKjrQ-4AxFDtNoNNj-7-=kXGT6RdOMOtyXUA>