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For first one:<br>
<br>
The rotation has file size limit so the file will never be bigger
than the limit. It used 'rewind' to reset the file pointer to start,
this will clear the end of file indicator too. Maybe this is the
reason the size showed is not correct? The time stamp in the file
indicates the end of log.<br>
<br>
Thanks<br>
Yumin<br>
<br>
<br>
<br>
On 12/20/2012 12:57 AM, лÁ¼ wrote:
<blockquote
cite="mid:DA8340397F7BAE41B8102757834CEB1222F94105@EX-MBOX2.xiaomi.net"
type="cite">
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<div style="direction: ltr;font-family: Tahoma;color:
#000000;font-size: 10pt;">Vm option :<br>
<font size="2"><span style="font-size: 10pt;">-Xmx49152m
-Xms49152m -Xmn1024m -Xss256k -XX:MaxDirectMemorySize=1024m
</span></font>-XX:+UseConcMarkSweepGC
-XX:+CMSDumpAtPromotionFailure -XX:+UseGCLogFileRotation
-XX:NumberOfGCLogFiles=100 -XX:GCLogFileSize=128m
<font size="2"><span style="font-size: 10pt;">-Xloggc:/home/work/log/hbase/ggsrv-miliao/regionserver/regionserver_gc.log
</span></font>...<br>
<br>
$java -version<br>
java version "1.6.0_37"<br>
Java(TM) SE Runtime Environment (build 1.6.0_37-b06)<br>
Java HotSpot(TM) 64-Bit Server VM (build 20.12-b01, mixed mode)<br>
<br>
After a promotion failure, there's an expected dump, but
there're two more things catch my eye :<br>
1) the dumped gc log size was not limited by GCLogFileSize
parameter<br>
<br>
-rw-rw-r-- 1 work work 2.7K Dec 20 12:12 regionserver_gc.log.2<br>
-rw-rw-r-- 1 work work <span style="font-weight: bold;">11499056168</span>
Dec 20 12:12 regionserver_gc.log.1<br>
-rw-rw-r-- 1 work work 77K Dec 20 16:21 regionserver_gc.log.0<br>
<br>
Looked into current codebase, seems the gc log rolling is
triggered in SafepointSynchronize::do_cleanup_tasks() only, if
we have huge dump info be written during a vm operation, the
GCLogFileSize limit is breakable<br>
<br>
2) Another weird problem is the PrintSafepointStatistics output
:<br>
<br>
vmop [threads: total
initially_running wait_to_block] [time: spin block sync
cleanup vmop] page_trap_count<br>
158282.484: GenCollectForAllocation [ 325
0 0 ] [ 0 0 0 2 113 ]
0<br>
vmop [threads: total
initially_running wait_to_block] [time: spin block sync
cleanup vmop] page_trap_count<br>
158283.141: GenCollectForAllocation [ 325
1 2 ] [ 0 0 0 2 112 ]
0<br>
vmop [threads: total
initially_running wait_to_block] [time: spin block sync
cleanup vmop] page_trap_count<br>
158283.766: GenCollectForAllocation [ 325
0 0 ] [ 0 0 0
<span style="font-weight: bold;">2543271 </span>] 0<br>
<br>
I could see 4 fields only at the last line, not 5, i'm a little
comfusued: )<br>
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