[CentOS] 6.2 x86_64 "mtrr_cleanup: can not find optimal value"

Hi,

I have server that has been running 5.x - 5.8 for a few years without issue and decided to move it to a fresh install of 6.2. First thing I noticed is a good part of the log has these mtrr messages finally ending with "mtrr_cleanup: can not find optimal value" and "please specify mtrr_gran_size/mtrr_chunk_size". I have been searching around and reading the kernel docs but are bit lost on the impact.

The system CPU is a q6600 so it supports mtrr. It has 8gb of RAM and a G33 intel chipset (maximum memory is 8gb), 256mb onboard Intel video. Problem exists with DVD 6.2 kernel and latest in yum update 2.6.32-220.7.1.el6.x86_64.

If I disable the Bios "memory remap feature", mtrr appears to have found it settings. But it says total ram covered is 7415M, so I lose some memory since when enabled it shows 8183M but mtrr fails. A little concerned about putting this back into production with this but hope to get it resolved rather than reinstall 5.8.

Will mtrr failing result in stability or performance loss? Is there any performance loss disabling memory remap in bios other than losing 600k? thx

Is this happening because the chipset only supports 8gb of memory and therefore mtrr cannot remap memory above 8gb? (assuming not since problem did not exist in 5.x centos)

-- Mike

Bios Memory remap feature: enabled

Apr 11 17:25:36 kernel: total RAM covered: 8183M Apr 11 17:25:36 kernel: gran_size: 64K chunk_size: 64K num_reg: 8 lose cover RAM: 4865M Apr 11 17:25:36 kernel: gran_size: 64K chunk_size: 128K num_reg: 8 lose cover RAM: 4865M Apr 11 17:25:36 kernel: gran_size: 64K chunk_size: 256K num_reg: 8 lose cover RAM: 4865M Apr 11 17:25:36 kernel: gran_size: 64K chunk_size: 512K num_reg: 8 lose cover RAM: 4865M Apr 11 17:25:36 kernel: gran_size: 64K chunk_size: 1M num_reg: 8 lose cover RAM: 4865M Apr 11 17:25:36 kernel: gran_size: 64K chunk_size: 2M num_reg: 8 lose cover RAM: 4864M Apr 11 17:25:36 kernel: gran_size: 64K chunk_size: 4M num_reg: 8 lose cover RAM: 4864M Apr 11 17:25:36 kernel: gran_size: 64K chunk_size: 8M num_reg: 8 lose cover RAM: 4864M Apr 11 17:25:36 kernel: gran_size: 64K chunk_size: 16M num_reg: 8 lose cover RAM: 0G Apr 11 17:25:36 kernel: gran_size: 64K chunk_size: 32M num_reg: 8 lose cover RAM: 0G Apr 11 17:25:36 kernel: gran_size: 64K chunk_size: 64M num_reg: 8 lose cover RAM: 0G Apr 11 17:25:36 kernel: gran_size: 64K chunk_size: 128M num_reg: 8 lose cover RAM: 0G Apr 11 17:25:36 kernel: gran_size: 64K chunk_size: 256M num_reg: 8 lose cover RAM: 0G Apr 11 17:25:36 kernel: *BAD*gran_size: 64K chunk_size: 512M num_reg: 8 lose cover RAM: -256M Apr 11 17:25:36 kernel: gran_size: 64K chunk_size: 1G num_reg: 8 lose cover RAM: 0G Apr 11 17:25:36 kernel: *BAD*gran_size: 64K chunk_size: 2G num_reg: 8 lose cover RAM: -1G Apr 11 17:25:36 kernel: gran_size: 128K chunk_size: 128K num_reg: 8 lose cover RAM: 4865M Apr 11 17:25:36 kernel: gran_size: 128K chunk_size: 256K num_reg: 8 lose cover RAM: 4865M Apr 11 17:25:36 kernel: gran_size: 128K chunk_size: 512K num_reg: 8 lose cover RAM: 4865M Apr 11 17:25:36 kernel: gran_size: 128K chunk_size: 1M num_reg: 8 lose cover RAM: 4865M Apr 11 17:25:36 kernel: gran_size: 128K chunk_size: 2M num_reg: 8 lose cover RAM: 4864M Apr 11 17:25:36 kernel: gran_size: 128K chunk_size: 4M num_reg: 8 lose cover RAM: 4864M Apr 11 17:25:36 kernel: gran_size: 128K chunk_size: 8M num_reg: 8 lose cover RAM: 4864M Apr 11 17:25:36 kernel: gran_size: 128K chunk_size: 16M num_reg: 8 lose cover RAM: 0G Apr 11 17:25:36 kernel: gran_size: 128K chunk_size: 32M num_reg: 8 lose cover RAM: 0G Apr 11 17:25:36 kernel: gran_size: 128K chunk_size: 64M num_reg: 8 lose cover RAM: 0G Apr 11 17:25:36 kernel: gran_size: 128K chunk_size: 128M num_reg: 8 lose cover RAM: 0G Apr 11 17:25:36 kernel: gran_size: 128K chunk_size: 256M num_reg: 8 lose cover RAM: 0G Apr 11 17:25:36 kernel: *BAD*gran_size: 128K chunk_size: 512M num_reg: 8 lose cover RAM: -256M Apr 11 17:25:36 kernel: gran_size: 128K chunk_size: 1G num_reg: 8 lose cover RAM: 0G Apr 11 17:25:36 kernel: *BAD*gran_size: 128K chunk_size: 2G num_reg: 8 lose cover RAM: -1G Apr 11 17:25:36 kernel: gran_size: 256K chunk_size: 256K num_reg: 8 lose cover RAM: 4865M Apr 11 17:25:36 kernel: gran_size: 256K chunk_size: 512K num_reg: 8 lose cover RAM: 4865M Apr 11 17:25:36 kernel: gran_size: 256K chunk_size: 1M num_reg: 8 lose cover RAM: 4865M Apr 11 17:25:36 kernel: gran_size: 256K chunk_size: 2M num_reg: 8 lose cover RAM: 4864M Apr 11 17:25:36 kernel: gran_size: 256K chunk_size: 4M num_reg: 8 lose cover RAM: 4864M Apr 11 17:25:36 kernel: gran_size: 256K chunk_size: 8M num_reg: 8 lose cover RAM: 4864M Apr 11 17:25:36 kernel: gran_size: 256K chunk_size: 16M num_reg: 8 lose cover RAM: 0G Apr 11 17:25:36 kernel: gran_size: 256K chunk_size: 32M num_reg: 8 lose cover RAM: 0G Apr 11 17:25:36 kernel: gran_size: 256K chunk_size: 64M num_reg: 8 lose cover RAM: 0G Apr 11 17:25:36 kernel: gran_size: 256K chunk_size: 128M num_reg: 8 lose cover RAM: 0G Apr 11 17:25:36 kernel: gran_size: 256K chunk_size: 256M num_reg: 8 lose cover RAM: 0G Apr 11 17:25:36 kernel: *BAD*gran_size: 256K chunk_size: 512M num_reg: 8 lose cover RAM: -256M Apr 11 17:25:36 kernel: gran_size: 256K chunk_size: 1G num_reg: 8 lose cover RAM: 0G Apr 11 17:25:36 kernel: *BAD*gran_size: 256K chunk_size: 2G num_reg: 8 lose cover RAM: -1G Apr 11 17:25:36 kernel: gran_size: 512K chunk_size: 512K num_reg: 8 lose cover RAM: 4865M Apr 11 17:25:36 kernel: gran_size: 512K chunk_size: 1M num_reg: 8 lose cover RAM: 4865M Apr 11 17:25:36 kernel: gran_size: 512K chunk_size: 2M num_reg: 8 lose cover RAM: 4864M Apr 11 17:25:36 kernel: gran_size: 512K chunk_size: 4M num_reg: 8 lose cover RAM: 4864M Apr 11 17:25:36 kernel: gran_size: 512K chunk_size: 8M num_reg: 8 lose cover RAM: 4864M Apr 11 17:25:36 kernel: gran_size: 512K chunk_size: 16M num_reg: 8 lose cover RAM: 0G Apr 11 17:25:36 kernel: gran_size: 512K chunk_size: 32M num_reg: 8 lose cover RAM: 0G Apr 11 17:25:36 kernel: gran_size: 512K chunk_size: 64M num_reg: 8 lose cover RAM: 0G Apr 11 17:25:36 kernel: gran_size: 512K chunk_size: 128M num_reg: 8 lose cover RAM: 0G Apr 11 17:25:36 kernel: gran_size: 512K chunk_size: 256M num_reg: 8 lose cover RAM: 0G Apr 11 17:25:36 kernel: *BAD*gran_size: 512K chunk_size: 512M num_reg: 8 lose cover RAM: -256M Apr 11 17:25:36 kernel: gran_size: 512K chunk_size: 1G num_reg: 8 lose cover RAM: 0G Apr 11 17:25:36 kernel: *BAD*gran_size: 512K chunk_size: 2G num_reg: 8 lose cover RAM: -1G Apr 11 17:25:36 kernel: gran_size: 1M chunk_size: 1M num_reg: 8 lose cover RAM: 4865M Apr 11 17:25:36 kernel: gran_size: 1M chunk_size: 2M num_reg: 8 lose cover RAM: 4864M Apr 11 17:25:36 kernel: gran_size: 1M chunk_size: 4M num_reg: 8 lose cover RAM: 4864M Apr 11 17:25:36 kernel: gran_size: 1M chunk_size: 8M num_reg: 8 lose cover RAM: 4864M Apr 11 17:25:36 kernel: gran_size: 1M chunk_size: 16M num_reg: 8 lose cover RAM: 0G Apr 11 17:25:36 kernel: gran_size: 1M chunk_size: 32M num_reg: 8 lose cover RAM: 0G Apr 11 17:25:36 kernel: gran_size: 1M chunk_size: 64M num_reg: 8 lose cover RAM: 0G Apr 11 17:25:36 kernel: gran_size: 1M chunk_size: 128M num_reg: 8 lose cover RAM: 0G Apr 11 17:25:36 kernel: gran_size: 1M chunk_size: 256M num_reg: 8 lose cover RAM: 0G Apr 11 17:25:36 kernel: *BAD*gran_size: 1M chunk_size: 512M num_reg: 8 lose cover RAM: -256M Apr 11 17:25:36 kernel: gran_size: 1M chunk_size: 1G num_reg: 8 lose cover RAM: 0G Apr 11 17:25:36 kernel: *BAD*gran_size: 1M chunk_size: 2G num_reg: 8 lose cover RAM: -1G Apr 11 17:25:36 kernel: gran_size: 2M chunk_size: 2M num_reg: 8 lose cover RAM: 4865M Apr 11 17:25:36 kernel: gran_size: 2M chunk_size: 4M num_reg: 8 lose cover RAM: 4865M Apr 11 17:25:36 kernel: gran_size: 2M chunk_size: 8M num_reg: 8 lose cover RAM: 4865M Apr 11 17:25:36 kernel: gran_size: 2M chunk_size: 16M num_reg: 8 lose cover RAM: 1M Apr 11 17:25:36 kernel: gran_size: 2M chunk_size: 32M num_reg: 8 lose cover RAM: 1M Apr 11 17:25:36 kernel: gran_size: 2M chunk_size: 64M num_reg: 8 lose cover RAM: 1M Apr 11 17:25:36 kernel: gran_size: 2M chunk_size: 128M num_reg: 8 lose cover RAM: 1M Apr 11 17:25:36 kernel: gran_size: 2M chunk_size: 256M num_reg: 8 lose cover RAM: 1M Apr 11 17:25:36 kernel: *BAD*gran_size: 2M chunk_size: 512M num_reg: 8 lose cover RAM: -255M Apr 11 17:25:36 kernel: gran_size: 2M chunk_size: 1G num_reg: 8 lose cover RAM: 1M Apr 11 17:25:36 kernel: *BAD*gran_size: 2M chunk_size: 2G num_reg: 8 lose cover RAM: -1023M Apr 11 17:25:36 kernel: gran_size: 4M chunk_size: 4M num_reg: 8 lose cover RAM: 771M Apr 11 17:25:36 kernel: gran_size: 4M chunk_size: 8M num_reg: 8 lose cover RAM: 4867M Apr 11 17:25:36 kernel: gran_size: 4M chunk_size: 16M num_reg: 8 lose cover RAM: 3M Apr 11 17:25:36 kernel: gran_size: 4M chunk_size: 32M num_reg: 8 lose cover RAM: 3M Apr 11 17:25:36 kernel: gran_size: 4M chunk_size: 64M num_reg: 8 lose cover RAM: 3M Apr 11 17:25:36 kernel: gran_size: 4M chunk_size: 128M num_reg: 8 lose cover RAM: 3M Apr 11 17:25:36 kernel: gran_size: 4M chunk_size: 256M num_reg: 8 lose cover RAM: 3M Apr 11 17:25:36 kernel: *BAD*gran_size: 4M chunk_size: 512M num_reg: 8 lose cover RAM: -253M Apr 11 17:25:36 kernel: gran_size: 4M chunk_size: 1G num_reg: 8 lose cover RAM: 3M Apr 11 17:25:36 kernel: *BAD*gran_size: 4M chunk_size: 2G num_reg: 8 lose cover RAM: -1021M Apr 11 17:25:36 kernel: gran_size: 8M chunk_size: 8M num_reg: 8 lose cover RAM: 263M Apr 11 17:25:36 kernel: gran_size: 8M chunk_size: 16M num_reg: 8 lose cover RAM: 263M Apr 11 17:25:36 kernel: gran_size: 8M chunk_size: 32M num_reg: 7 lose cover RAM: 7M Apr 11 17:25:36 kernel: gran_size: 8M chunk_size: 64M num_reg: 7 lose cover RAM: 7M Apr 11 17:25:36 kernel: gran_size: 8M chunk_size: 128M num_reg: 7 lose cover RAM: 7M Apr 11 17:25:36 kernel: gran_size: 8M chunk_size: 256M num_reg: 7 lose cover RAM: 7M Apr 11 17:25:36 kernel: gran_size: 8M chunk_size: 512M num_reg: 8 lose cover RAM: 7M Apr 11 17:25:36 kernel: gran_size: 8M chunk_size: 1G num_reg: 7 lose cover RAM: 7M Apr 11 17:25:36 kernel: gran_size: 8M chunk_size: 2G num_reg: 8 lose cover RAM: 7M Apr 11 17:25:36 kernel: gran_size: 16M chunk_size: 16M num_reg: 8 lose cover RAM: 263M Apr 11 17:25:36 kernel: gran_size: 16M chunk_size: 32M num_reg: 7 lose cover RAM: 7M Apr 11 17:25:36 kernel: gran_size: 16M chunk_size: 64M num_reg: 7 lose cover RAM: 7M Apr 11 17:25:36 kernel: gran_size: 16M chunk_size: 128M num_reg: 7 lose cover RAM: 7M Apr 11 17:25:36 kernel: gran_size: 16M chunk_size: 256M num_reg: 7 lose cover RAM: 7M Apr 11 17:25:36 kernel: gran_size: 16M chunk_size: 512M num_reg: 8 lose cover RAM: 7M Apr 11 17:25:36 kernel: gran_size: 16M chunk_size: 1G num_reg: 7 lose cover RAM: 7M Apr 11 17:25:36 kernel: gran_size: 16M chunk_size: 2G num_reg: 8 lose cover RAM: 7M Apr 11 17:25:36 kernel: gran_size: 32M chunk_size: 32M num_reg: 8 lose cover RAM: 23M Apr 11 17:25:36 kernel: gran_size: 32M chunk_size: 64M num_reg: 7 lose cover RAM: 23M Apr 11 17:25:36 kernel: gran_size: 32M chunk_size: 128M num_reg: 7 lose cover RAM: 23M Apr 11 17:25:36 kernel: gran_size: 32M chunk_size: 256M num_reg: 7 lose cover RAM: 23M Apr 11 17:25:36 kernel: gran_size: 32M chunk_size: 512M num_reg: 8 lose cover RAM: 23M Apr 11 17:25:36 kernel: gran_size: 32M chunk_size: 1G num_reg: 7 lose cover RAM: 23M Apr 11 17:25:36 kernel: gran_size: 32M chunk_size: 2G num_reg: 8 lose cover RAM: 23M Apr 11 17:25:36 kernel: gran_size: 64M chunk_size: 64M num_reg: 7 lose cover RAM: 55M Apr 11 17:25:36 kernel: gran_size: 64M chunk_size: 128M num_reg: 7 lose cover RAM: 55M Apr 11 17:25:36 kernel: gran_size: 64M chunk_size: 256M num_reg: 7 lose cover RAM: 55M Apr 11 17:25:36 kernel: gran_size: 64M chunk_size: 512M num_reg: 8 lose cover RAM: 55M Apr 11 17:25:36 kernel: gran_size: 64M chunk_size: 1G num_reg: 7 lose cover RAM: 55M Apr 11 17:25:36 kernel: gran_size: 64M chunk_size: 2G num_reg: 8 lose cover RAM: 55M Apr 11 17:25:36 kernel: gran_size: 128M chunk_size: 128M num_reg: 6 lose cover RAM: 119M Apr 11 17:25:36 kernel: gran_size: 128M chunk_size: 256M num_reg: 7 lose cover RAM: 119M Apr 11 17:25:36 kernel: gran_size: 128M chunk_size: 512M num_reg: 8 lose cover RAM: 119M Apr 11 17:25:36 kernel: gran_size: 128M chunk_size: 1G num_reg: 7 lose cover RAM: 119M Apr 11 17:25:36 kernel: gran_size: 128M chunk_size: 2G num_reg: 8 lose cover RAM: 119M Apr 11 17:25:36 kernel: gran_size: 256M chunk_size: 256M num_reg: 5 lose cover RAM: 247M Apr 11 17:25:36 kernel: gran_size: 256M chunk_size: 512M num_reg: 5 lose cover RAM: 247M Apr 11 17:25:36 kernel: gran_size: 256M chunk_size: 1G num_reg: 5 lose cover RAM: 247M Apr 11 17:25:36 kernel: gran_size: 256M chunk_size: 2G num_reg: 6 lose cover RAM: 247M Apr 11 17:25:36 kernel: gran_size: 512M chunk_size: 512M num_reg: 4 lose cover RAM: 503M Apr 11 17:25:36 kernel: gran_size: 512M chunk_size: 1G num_reg: 5 lose cover RAM: 503M Apr 11 17:25:36 kernel: gran_size: 512M chunk_size: 2G num_reg: 6 lose cover RAM: 503M Apr 11 17:25:36 kernel: gran_size: 1G chunk_size: 1G num_reg: 3 lose cover RAM: 1015M Apr 11 17:25:36 kernel: gran_size: 1G chunk_size: 2G num_reg: 3 lose cover RAM: 1015M Apr 11 17:25:36 kernel: gran_size: 2G chunk_size: 2G num_reg: 2 lose cover RAM: 2039M Apr 11 17:25:36 kernel: mtrr_cleanup: can not find optimal value Apr 11 17:25:36 kernel: please specify mtrr_gran_size/mtrr_chunk_size

cat /proc/mtrr reg00: base=0x0d0000000 ( 3328MB), size= 256MB, count=1: uncachable reg01: base=0x0e0000000 ( 3584MB), size= 512MB, count=1: uncachable reg02: base=0x000000000 ( 0MB), size= 8192MB, count=1: write-back reg03: base=0x200000000 ( 8192MB), size= 512MB, count=1: write-back reg04: base=0x220000000 ( 8704MB), size= 256MB, count=1: write-back reg05: base=0x0cf700000 ( 3319MB), size= 1MB, count=1: uncachable reg06: base=0x0cf800000 ( 3320MB), size= 8MB, count=1: uncachable

cat /proc/meminfo MemTotal: 8050140 kB

Now with: Bios Memory remap feature: disabled

cat /proc/meminfo MemTotal: 7276000 kB

Apr 11 15:33:41 ns2 kernel: total RAM covered: 7415M

Apr 11 15:33:41 ns2 kernel: Found optimal setting for mtrr clean up

Apr 11 15:33:41 ns2 kernel: gran_size: 64K chunk_size: 16M num_reg: 6 lose cover RAM: 0G

/proc/mtrr (bios memory remap disabled)

reg00: base=0x000000000 ( 0MB), size= 2048MB, count=1: write-back

reg01: base=0x080000000 ( 2048MB), size= 1024MB, count=1: write-back

reg02: base=0x0c0000000 ( 3072MB), size= 256MB, count=1: write-back

reg03: base=0x0cf700000 ( 3319MB), size= 1MB, count=1: uncachable

reg04: base=0x0cf800000 ( 3320MB), size= 8MB, count=1: uncachable

reg05: base=0x100000000 ( 4096MB), size= 4096MB, count=1: write-back

reg06: base=0x0d0000000 ( 3328MB), size= 256MB, count=1: write-combining