Anyone know about FreeBSD file system tuning? - GoFuckYourself.com

rowan · 11-29-2007, 10:37 PM

Basically I'm trying to figure out how to increase this:

Mem: 39M Active, 509M Inact, 234M Wired, 28K Cache, 112M Buf, 1221M Free

I've checked 5 different servers and they all have a value of around 112MB used for buffering, even though the physical RAM varies from 1GB - 4GB

Tried increasing maxusers but that hasn't changed anything, buf still tops out at 112MB

How do I get FreeBSD to use more memory for disk caching?

GrouchyAdmin · 11-29-2007, 11:17 PM

Do a make lint in the source tree and look; I'm pretty damn sure that there is still an FFS/UFS cache as well as directory hashing SOFTUPDATES. I haven't done bare-wire tuning with any of the recent 5.x tree, though. You're probably going to want to increase your stack as well.

Look here for more updated information.

rvn · 11-30-2007, 12:14 AM

freebsd.org/doc/en_US.ISO8859-1/books/handbook/configtuning-disk.html

wanted · 11-30-2007, 12:15 AM

docs + manual (man) is always the way to go

V_RocKs · 11-30-2007, 12:42 AM

Bump for answers.

rowan · 11-30-2007, 02:09 AM

Thanks for the replies but so far none actually address how to increase the maximum size allocated for buffering (which is vfs.maxbufspace)

I've tried changing the BKVASIZE value (in sys/param.h) from 16384 to 32768, but I'm not sure whether that actually allocates more buffers or just larger ones.

rowan · 11-30-2007, 07:23 AM

"options NBUF=16384" in the kernel config seems to have done the trick, memory used now floats up to 255MB.

I tried to go further but ended up with a kernel panic. This will do for now.

11-29-2007, 10:37 PM	#1
rowan Too lazy to set a custom title Join Date: Mar 2002 Location: Australia Posts: 17,393	Anyone know about FreeBSD file system tuning? Basically I'm trying to figure out how to increase this: Mem: 39M Active, 509M Inact, 234M Wired, 28K Cache, 112M Buf, 1221M Free I've checked 5 different servers and they all have a value of around 112MB used for buffering, even though the physical RAM varies from 1GB - 4GB Tried increasing maxusers but that hasn't changed anything, buf still tops out at 112MB How do I get FreeBSD to use more memory for disk caching?

11-29-2007, 11:17 PM	#2
GrouchyAdmin Now choke yourself! Industry Role: Join Date: Apr 2006 Posts: 12,085	Do a make lint in the source tree and look; I'm pretty damn sure that there is still an FFS/UFS cache as well as directory hashing SOFTUPDATES. I haven't done bare-wire tuning with any of the recent 5.x tree, though. You're probably going to want to increase your stack as well. Look here for more updated information. __________________ AIM: GrouchyGfy

11-30-2007, 12:14 AM	#3
rvn Confirmed User Join Date: Sep 2006 Location: Ukraine/USA Posts: 176	freebsd.org/doc/en_US.ISO8859-1/books/handbook/configtuning-disk.html __________________ These things are good

11-30-2007, 12:15 AM	#4
wanted Certified Asshole Industry Role: Join Date: Jan 2003 Location: In front of my laptop. Posts: 896	docs + manual (man) is always the way to go __________________ Living the dream.

11-30-2007, 12:42 AM	#5
V_RocKs Damn Right I Kiss Ass! Industry Role: Join Date: Dec 2003 Location: Cowtown, USA Posts: 32,422	Bump for answers.

11-30-2007, 02:09 AM	#6
rowan Too lazy to set a custom title Join Date: Mar 2002 Location: Australia Posts: 17,393	Thanks for the replies but so far none actually address how to increase the maximum size allocated for buffering (which is vfs.maxbufspace) I've tried changing the BKVASIZE value (in sys/param.h) from 16384 to 32768, but I'm not sure whether that actually allocates more buffers or just larger ones.

11-30-2007, 07:23 AM	#7
rowan Too lazy to set a custom title Join Date: Mar 2002 Location: Australia Posts: 17,393	"options NBUF=16384" in the kernel config seems to have done the trick, memory used now floats up to 255MB. I tried to go further but ended up with a kernel panic. This will do for now.