one simple persistence record is about 112 bytes. anyway, you may grep "persist" from "b memory", "tmsh show sys memory" or "tmctl memory_usage_stat" command output.
sol5779: The amount of memory the BIG-IP LTM allocates for a simple persistence record
https://support.f5.com/kb/en-us/solutions/public/5000/700/sol5779.html
by the way, you are not running 10.x, are you?
sol10094: Running the 'bigpipe persist show' command on a system with a large number of persistent connections can cause system instability
http://support.f5.com/kb/en-us/solutions/public/10000/000/sol10094.html
[root@ve10:Active] config tmsh list ltm virtual bar
ltm virtual bar {
destination 172.28.19.252:http
ip-protocol tcp
mask 255.255.255.255
persist {
source_addr {
default yes
}
}
pool foo
profiles {
http { }
tcp { }
}
snat automap
}
no persistence record
[root@ve10:Active] config b persist
No Persistence Table Entries were found.
[root@ve10:Active] config tmsh show sys memory|grep -i "subsystem\|persist"
Sys::SubSystem Memory
SubSystem Alloc (bytes) Max Alloc (bytes) Object Size
http_persist 0 0 72
persist 0 0 112
persistence (variable) 0 0 1
1 persistence record
[root@ve10:Active] config b persist
PERSISTENT CONNECTIONS
Type Virtual Node
source addr 172.28.19.252:80 200.200.200.101:80
[root@ve10:Active] config tmsh show sys memory|grep -i "subsystem\|persist"
Sys::SubSystem Memory
SubSystem Alloc (bytes) Max Alloc (bytes) Object Size
http_persist 0 0 72
persist 112 112 112
persistence (variable) 0 0 1
Nimbostratus
