PrintGCStats

[Peter B. Kessler]

It looks like the most recent PrintGCFixup (and PrintGCStats
and CompareGCStats) is "posted" in

     http://permalink.gmane.org/gmane.comp.java.openjdk.hotspot.gc.devel/51

You have to join all the lines that got wrapped (sigh).
Sometimes you have to run PrintGCFixup more than once to
get it to remove things so that it can see other things
to remove.  Though, in your case, running it twice doesn't
help remove the output of PrintFLSStatistics.  It does look
like if you add a cleaner for PrintFLSStatistics, you'll
have to run PrintGCFixup at least twice, since that output
gets in the way of the removal of the PrintTenuringDistribution
flag.

PrintGCFixup and friends look like a prime candidate for putting
in hotspot/tools/ and letting people make improvements.  If you
wanted to contribute your addition for removing PrintFLSStatistics,
I'm sure we could find someone here to sponsor it.

			... peter

Naas, Dave wrote:

> Regarding the posting from Oct 26, 2007:  http://mail.openjdk.java.net/pipermail/hotspot-gc-dev/2007-October/000064.html	
> where Mr. Kessler states: 
> quote 
> 	> > I'll see if we can get an updated version of PrintGCStats out to replace the ancient one available at 
> 	> >	 <http://java.sun.com/developer/technicalArticles/Programming/turbo/> 
> 	> > That should give you the kinds of statistics you are asking for. 
> 	> > 	... peter 
> unquote
> 
> I was wondering if a new version of PrintGCStats and PrintGCFixup will indeed be made available or if we should proceed with our own updates to handle new jdk releases, etc.??    
> 
> A specific, recent example is jdk 1.6 with the -XX:PrintFLSStatistics flag.  We have found that this setting prevents the current PrintGCStats from properly parsing ParNew data and thus doesn't generate the Promotion stats (Promo.csv file).   The following snippet shows how the ParNew line is now split (shown in bold), thanks to the -XX:PrintFLSStatistics:  
> 
> ======================================================================================================================================================
> {Heap before GC invocations=0 (full 0):
>  par new generation   total 305088K, used 277376K [0x2f800000, 0x43d00000, 0x43d00000)
>   eden space 277376K, 100% used [0x2f800000, 0x406e0000, 0x406e0000)
>   from space 27712K,   0% used [0x406e0000, 0x406e0000, 0x421f0000)
>   to   space 27712K,   0% used [0x421f0000, 0x421f0000, 0x43d00000)
>  concurrent mark-sweep generation total 2739200K, used 0K [0x43d00000, 0xeb000000, 0xeb000000)
>  concurrent-mark-sweep perm gen total 131072K, used 14913K [0xeb000000, 0xf3000000, 0xfb000000)
> 8.746: [GC Before GC:
> Statistics for BinaryTreeDictionary:
> ------------------------------------
> Total Free Space: 701235200
> Max   Chunk Size: 701235200
> Number of Blocks: 1
> Av.  Block  Size: 701235200
> Tree      Height: 1
> Before GC:
> Statistics for BinaryTreeDictionary:
> ------------------------------------
> Total Free Space: 0
> Max   Chunk Size: 0
> Number of Blocks: 0
> Tree      Height: 0
> 8.746: [ParNew
> Desired survivor size 14188544 bytes, new threshold 1 (max 4)
> - age   1:   15763640 bytes,   15763640 total
> - age   2:         56 bytes,   15763696 total
> : 277376K->15474K(305088K), 0.5657873 secs] 277376K->15474K(3044288K)After GC:
> Statistics for BinaryTreeDictionary:
> ------------------------------------
> Total Free Space: 701218816
> Max   Chunk Size: 701218816
> Number of Blocks: 1
> Av.  Block  Size: 701218816
> Tree      Height: 1
> After GC:
> Statistics for BinaryTreeDictionary:
> ------------------------------------
> Total Free Space: 0
> Max   Chunk Size: 0
> Number of Blocks: 0
> Tree      Height: 0
> , 0.5668866 secs] [Times: user=0.34 sys=1.07, real=0.57 secs]
> ======================================================================================================================================================
> 
> Thank you, 
> Dave 
> 
>  David Naas
> Chicago Board Options Exchange 
>  312-786-7222
>