Exhausted resources

Systemtap attempts to assure that probe handlers run within strict time/space limits. A typical script producing a modest amount of trace data will not encounter these limits, but maybe your script does. What can you do?

A blunt workaround is to use the --suppress-handler-errors flag. It lets most errors be quietly absorbed by the systemtap runtime, so the script will soldier on and on, until it runs exit(), or a user interrupts it. It'll print a single warning message then.

It depends on what resource ran out.

error message	exhausted resource	possible remedy
MAXACTION exceeded	time -- number of statements executed by probe handler	recompile with larger -DMAXACTION=NN or -DMAXACTION_INTERRUPTIBLE=NN
		impose limits on iteration - foreach (... limit NN) or break)
MAXNESTING exceeded	time/space -- function recursion too deep	reduce recursion
		recompile with larger -DMAXNESTING=NN
division by zero	time/space -- universe is too small to represent exact value	try dividing by one instead
aggregation overflow	space -- number of distinct index tuples in aggregation array	recompile with larger -DMAXMAPENTRIES=NN
		declare that array only with larger size -- global my_array[NN]
		delete unneeded elements, or use % array global declaration suffix
Array overflow	space -- number of distinct index tuples in ordinary array	as above
string truncation	space -- strings are silently limited to a maximum length	recompile with larger -DMAXSTRINGLEN=NN
WARNING: ... skipped probes: NN	time -- cross-processor contention over global script variables	reduce number of globals
		maybe recompile with larger -DMAXTRYLOCK=NN
		use aggregates and @count() instead of integer counters
	various tolerable transient conditions	retry with larger -DMAXSKIPPED=NN
	space -- too many return probes may be pending	add larger .maxaction(NN) to .return probe point
	space -- too little kernel stack available for probe handler run	risky, but maybe recompile with smaller -DMINSTACKSPACE=NN
probe overhead exceeded threshold	time -- probe handlers are taking too high fraction of total real time	shrink probe handler code
		recompile with larger -DSTP_OVERLOAD_THRESHOLD
		disable this heuristic with -g --suppress-time-limits
There were NN transport failures	space -- amount of data printed by script exceeded staprun's capability to copy it to the output file	print less stuff
		run with larger trace buffers: stap -s NN
out-of-memory during or after startup	space -- large arrays?	recompile with smaller -DMAXSTRINGLEN, if string indexes
		recompile with smaller -DMAXMAPENTRIES or global foo[SIZE]
		join index columns into single string with sprintf()
		use smaller kernel boot maxcpus=NNN if kernel reserves excess hotplug slots
		use scalar (++) rather than aggregate (<<<1; @count) arrays