ANALYZE(8) System Manager's Manual ANALYZE(8)
analyze - Virtual UNIX postmortem crash analyzer
/etc/analyze [ -s swapfile ] [ -f ] [ -m ] [ -d ] [ -D ] [ -v ] core-
file [ system ]
Analyze is the post-mortem analyzer for the state of the paging system.
In order to use analyze you must arrange to get a image of the memory
(and possibly the paging area) of the system after it crashes (see
The analyze program reads the relevant system data structures from the
core image file and indexing information from /vmunix (or the specified
file) to determine the state of the paging subsystem at the point of
crash. It looks at each process in the system, and the resources each
is using in an attempt to determine inconsistencies in the paging sys-
tem state. Normally, the output consists of a sequence of lines show-
ing each active process, its state (whether swapped in or not), its
p0br, and the number and location of its page table pages. Any pages
which are locked while raw i/o is in progress, or which are locked
because they are intransit are also printed. (Intransit text pages
often diagnose as duplicated; you will have to weed these out by hand.)
The program checks that any pages in core which are marked as not modi-
fied are, in fact, identical to the swap space copies. It also checks
for non-overlap of the swap space, and that the core map entries corre-
spond to the page tables. The state of the free list is also checked.
Options to analyze:
-D causes the diskmap for each process to be printed.
-d causes the (sorted) paging area usage to be printed.
-f which causes the free list to be dumped.
-m causes the entire coremap state to be dumped.
-v (long unused) which causes a hugely verbose output format to be
In general, the output from this program can be confused by processes
which were forking, swapping, or exiting or happened to be in unusual
states when the crash occurred. You should examine the flags fields of
relevant processes in the output of a pstat(8) to weed out such pro-
It is possible to look at the core dump with adb if you do
adb -k /vmunix /vmcore
/vmunix default system namelist
adb(1), ps(1), crash(8V), pstat(8)
Ozalp Babaoglu and William Joy
Various diagnostics about overlaps in swap mappings, missing swap map-
pings, page table entries inconsistent with the core map, incore pages
which are marked clean but differ from disk-image copies, pages which
are locked or intransit, and inconsistencies in the free list.
It would be nice if this program analyzed the system in general, rather
than just the paging system in particular.
4th Berkeley Distribution 4 February 1983 ANALYZE(8)