I would like some hints regarding the maximum size of mfs.
mount_mfs(8) says:
Note however that for mount_mfs the practical limit is based
on datasize in login.conf(5), and ultimately depends on the per-
arch MAXDSIZ limit.
So, I searched for the MAXDSIZ value in the source code.
# cd /usr/src/sys/arch
# grep -rs 'define[ ]*MAXDSIZ' amd64 arm64 i386
amd64/include/vmparam.h:#define MAXDSIZ ((paddr_t)32*1024*1024*1024) /*
max data size */
arm64/include/vmparam.h:#define MAXDSIZ ((paddr_t)16*1024*1024*1024) /*
max data size */
i386/include/vmparam.h:#define MAXDSIZ (3UL*1024*1024*1024) /* max data
size */
I found that it is defined as 32GB for amd64, 16GB for arm64, and 3GB
for i386.
When I try mfs mount on each architecture, I generally get the
capacity specified by the kernel on amd64 and arm64, but on i386, the
limit is reached with a value much smaller than MAXDSIZ.
As you can see, I set each resource value to the maximum with
ulimit. The data size is set to 3 GB.
# ulimit -a
time(cpu-seconds) unlimited
file(blocks) unlimited
coredump(blocks) unlimited
data(kbytes) 3145728
stack(kbytes) 8192
lockedmem(kbytes) unlimited
memory(kbytes) 3838984
nofiles(descriptors) 128
processes 1310
However, when I run the mfs mount, the maximum value is a little
larger than 1GB.
# mount -t mfs -o -s=1351M swap /mnt
# umount /mnt
# mount -t mfs -o -s=1352M swap /mnt
mount_mfs: mmap: Cannot allocate memory
What could be the cause? Is there any way to increase the MAXDSIZ to
nearly 3GB?
----
Yoshihiro Kawamata
http://fuguita.org/
