Trying to NOT run out of gem space while having a decent profiling sample resolution

Hi guys, 

Allen Otis suggested me a nice idea to use #computeInterval: so that I can get a decent number of samples based on the approx total time rather than a fixed interval value. The problem is, of course, the higher the sampling, the more gem temp space I need. I already increased my gem temp space quite a bit, but for certain scenarios I am still running out of memory. Basically, the profiler outputs:

There was an error trying to profile: a Error occurred (error 2517), 2 failed attempts to signal AlmostOutOfMemory

So... besides the obvious solution of increase and increasing and increasing the gem temp space, I tried something similar to what I do with sixx...basically.. make that temp space to be persistence and do the stuff inside a memory handler that commits under pressure.

My code looks like this:

profile: aBlock estimatedTotalCpuTime: totalCpuTime tallyThreshold: tallyThreshold writingReportOn: aStream

  "Profiles aBlock with a sample of miliseconds and writes the resulting report (limited to tallyThreshold number of invokations of a given method) into aStream "

  | profMon startTime endTime persistentKey persistentDict |

  persistentKey := ('PROFMONITOR' , Object new identityHash asString) asSymbol.

  persistentDict := UserGlobals

    at: #'ProfMonitorRoots'

    ifAbsentPut: [ RcKeyValueDictionary new ].

  [ 

  FACompatibilityUtils current

    commitOnAlmostOutOfMemoryDuring: [ 

      startTime := System _timeGmtFloat.

      profMon := ProfMonitorTree new.

      persistentDict at: persistentKey put: profMon.

      profMon intervalNs: (profMon class computeInterval: totalCpuTime) * 4.

      profMon startMonitoring.

      [ aBlock value ]

        ensure: [ 

          "This #ensure: is very important because the closure we are profiling may raise a signal... (like seaside request processing which uses notifications)..so without the #ensure: we do not write the report anywhere..."

          [ 

          endTime := System _timeGmtFloat.

          profMon stopMonitoring.

          profMon gatherResults.

          aStream

            nextPutAll:

                'Total time: ' , ((endTime - startTime) * 1000) asInteger asString;

            cr;

            cr.

          aStream

            nextPutAll: (profMon reportDownTo: tallyThreshold);

            cr.

          profMon removeResults ]

            on: Error

            do: [ :ex | aStream nextPutAll: 'There was an error trying to profile: ' , ex printString ] ] ]

    threshold: 80 ]

    ensure: [ 

      persistentDict removeKey: persistentKey ifAbsent: [  ].

      System commit ]

What I cannot understand is that WITHOUT the #commitOnAlmostOutOfMemoryDuring:threshold:   logic, I only get the out of memory problem in a few scenarios (those scenarios that are really big). 

Now, WITH the logic of  #commitOnAlmostOutOfMemoryDuring:threshold: I thought I should get none (ideally) out of memory problem as the samples are now persistent. Yet... the funny part is that I am getting above error for every single profile I do..even for small ones. WTF!  

I am clearly doing something wrong, but I cannot see it.

What does it mean exactly the exception " 2 failed attempts to signal AlmostOutOfMemory" ????  How can someone fail to signal the exception ? What can I do so that it doesn't fail ?