Description

This article describes the issue of the file system storage capacity, for packages/mfs-jkernel-ex, being at 102%.

Symptoms

The file system storage capacity for  packages/mfs-jkernel-ex is at 102 % , on EX4200, EX4500, and EX8200.


Solution


The fs_minfree element provides the minimum acceptable percentage of file system blocks that may be free. If the free list drops below this level, only the super-user can continue to allocate blocks.

The fs_minfree element may be set to 0 , if no reserve of free blocks seems necessary; however severe performance degradations will be observed, if the file system is run greater than 92% to 90% full. So the default value of fs_minfree is 8% to 10%.

Now, when running the Show System Storage command:



root@DND> show system storage

Filesystem Size Used Avail Capacity Mounted on
/dev/da0s1a 731M 160M 512M 24% /
devfs 1.0K 1.0K 0B 100% /dev
/dev/md0 37M 37M 0B 100% /packages/mnt/jbase
/dev/md1 12M 7.3M 3.6M 67% /packages/mfs-jcrypto-ex
/dev/md2 22M 22M 0B 100% /packages/mnt/jcrypto-ex-11.1R3.5
/dev/md3 8.7M 4.1M 3.9M 51% /packages/mfs-jdocs-ex
/dev/md4 6.3M 6.3M 0B 100% /packages/mnt/jdocs-ex-11.1R3.5
/dev/md5 64M 61M -1.4M 102% /packages/mfs-jkernel-ex
/dev/md6 162M 162M 0B 100% /packages/mnt/jkernel-ex-11.1R3.5
/dev/md7 31M 26M 1.9M 93% /packages/mfs-jpfe-ex82x


The full size is shown as 64M and used is shown as 61M; this means that 64-61= 3M space is still remaining; but, it shows the available space as -1.4M .
 
As mentioned above, you cannot have more than 92% to 90% space. This means 8% to 10% is held or obstructed by fs_minfree .

Now, 61-1.4 = 59.6M And (61*100)/59.6=102.34%, which is nothing but the over reached capacity.

As 8% to 10% of 64M will be between 58.88M to 57.60M and you can see the value above is shown as 59.6M, which is exceeding the limit obstruct by fs_minfree .

Till now, no problem has been observed in terms of performance; but according to FreeBSD , performance degradations can be observed.