#umascan Intrumentation tool for FreeBSD's Unified Memory Allocation (UMA).
umascan [-v] [-n dumpnr | -c core] [-k kernel] (-s addr | -z probs)
The umascan utility is an instrumentation tool based on kvm, which scans a list of pointers (from a file or from a list of dtrace probes) in the UMA's allocated memory. It can be used with the live kernel or with a core file. It displays the zone name where the pointer is located, the total count of references (by zone name), and the value of its reference count field if the structure has this field.
The options are as follows:
-c core
Explicitly select the core dump file to be used.
-n dumpnr
Use the kernel core dump file numbered dumpnr.
-k kernel
Select the kernel symbol file to be used. If no kernel symbol file is given, the
symbol file of the currently running kernel will be used.
-s addr
Scan pointers in file file addrs.
-z probs
Run dtrace with the probes selected and scan the pointers retrieved by dtrace.
-v
Increase verbosity.
The -c and -n (-s and -z) options are mutually exclusive. If no core dump file
is specified through any options, /dev/mem will be opened to allow scanning the
currently running kernel.
./umascan -c /var/crash/vmcore.0 -s ucred.list
umascan: input file: ucred.list
umascan: core file: /var/crash/vmcore.0
umascan: kernel image: /usr/obj/usr/src/sys/GENERIC/kernel.debug
0xfffff80002db4a00:
zone name: 256
ref count: 45
total count: 15
Files: 12
PROC: 3