Limit for swapspace?

Hi there,

I've got created swapspace on one of my two zpools

Code:
zfs create -V 48G satapool/swap
zfs set checksum=off satapool/swap
zfs set org.freebsd:swap=on satapool/swap

After restarting the box top shows me only 32 GB Swap. Is there a limit for swap?
Currently they are only 24 GB memory installed. But on later time it will comes more.
 
Check out the kern.maxswzone sysctl variable.

I happen to use 32GB on one drive and 16GB on another, but you could tune that variable to allow more. It should be in KBs (currently/default on amd64-9.0 it's 33554432).

-Brandon Falk
 
falkman said:
Check out the kern.maxswzone sysctl variable.

I happen to use 32GB on one drive and 16GB on another, but you could tune that variable to allow more. It should be in KBs (currently/default on amd64-9.0 it's 33554432).

-Brandon Falk
In the manpage from sysctl is nothing inside about kern.maxswzone. Where I could read more about the information?
 
/usr/src/

Code:
$ cd /usr/src
$ ack maxswzone
[FILE]sys/kern/subr_param.c[/FILE]
90:long	maxswzone;			/* max swmeta KVA storage */
109:SYSCTL_LONG(_kern, OID_AUTO, maxswzone, CTLFLAG_RDTUN, &maxswzone, 0,
214:	maxswzone = VM_SWZONE_SIZE_MAX;
216:	TUNABLE_LONG_FETCH("kern.maxswzone", &maxswzone);

[FILE]sys/sys/buf.h[/FILE]
451:extern long	maxswzone;		/* Max KVA for swap structures */

[FILE]sys/i386/include/param.h[/FILE]
123: * the kern.maxswzone /boot/loader.conf variable.

[FILE]sys/vm/swap_pager.c[/FILE]
517:	if (maxswzone && n > maxswzone / sizeof(struct swblock))
518:		n = maxswzone / sizeof(struct swblock);
1855:				printf("swap zone exhausted, increase kern.maxswzone\n");

[FILE]sys/amd64/include/param.h[/FILE]
135: * the kern.maxswzone /boot/loader.conf variable.

For clues take a look in these files...
 
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