Meaning of results for command "get hardware memory"

[Dirk_Ehlers]

Hello,

If I run the command "get hardware memory" on a FGT 100D I get this output:

        total:    used:    free:  shared: buffers:  cached: shm:

Mem:  4146601984 1700696064 2445905920        0 145674240 671895552 328130560

Swap:        0        0        0

MemTotal:        4049416 kB

MemFree:         2411416 kB

MemShared:     0 kB

Buffers:            142260 kB

Cached:           654284 kB

SwapCached:   0 kB

Active:             291276 kB

Inactive:           505368 kB

HighTotal:         0 kB

HighFree:         0 kB

LowTotal:         4049416 kB

LowFree:          2411416 kB

SwapTotal:       0 kB

SwapFree:        0 kB

All infos I found are that MemTotal = HighTotal + LowTotal, HighTotal belongs to a zone ZONE_HIGHMEM, LowFree belongs to a zone ZONE_NORMAL. Does somebody know whats the meaning of HighTotal, HighFree, LowTotal, LowFree and this zones ?

Have these values something to do with shared memory and conserve mode ?

regards

Dirk Ehlers

[jmlux]

To understand the zones you may want to brush up on Linux Memory Management. I doubt however that a Fortigate would use memory like a normal Linux system, that is fill all available memory with I/O cache and stuff (that's what the link is about, so you should ignore that part). Certainly, the FG has better things to do with memory. However the basic memory structure and zones probably are the same as with any common Linux system. Why would they reinvent the wheel :)

[vjoshi_FTNT]

Hello Dirk,

High Memory is the segment of memory that user-space programs can address. It can also be accessed indirectly by Kernel programs.

Low Memory is the segment of memory that the Linux kernel can address directly. It is protected from user mode programs.

Please refer to the below KB article which explains the memory management very well:

http://kb.fortinet.com/kb/microsites/search.do?cmd=displayKC&docType=kc&externalId=FD35192