Re: [jira] Created: (JCS-73) concurrent cache access causes values loss

The group functionality will be deprecated.  It's already unofficially depr=
ecated.  Most of the auxiliaries don't support it.  . . . But I look into i=
t.=0A=0AAaron=0A=0A--- On Wed, 4/14/10, Alexander Kleymenov (JIRA) <jira@ap=
ache.org> wrote:=0A=0A> From: Alexander Kleymenov (JIRA) <[email protected]>=
=0A> Subject: [jira] Created: (JCS-73) concurrent cache access causes value=
s loss=0A> To: [email protected]=0A> Date: Wednesday, April 14, 20=
10, 9:27 PM=0A> concurrent cache access causes values=0A> loss=0A> --------=
----------------------------------=0A> =0A> =A0 =A0 =A0 =A0 =A0 =A0 =A0=0A>=
 =A0=A0=A0Key: JCS-73=0A> =A0 =A0 =A0 =A0 =A0 =A0 =A0=0A> =A0=A0=A0URL: htt=
ps://issues.apache.org/jira/browse/JCS-73=0A> =A0 =A0 =A0 =A0 =A0=0A> =A0=
=A0=A0Project: JCS=0A> =A0 =A0 =A0 =A0 =A0 Issue Type: Bug=0A> =A0 =A0 =A0 =
=A0 =A0 Components: Indexed Disk=0A> Cache=0A> =A0 =A0 Affects Versions: jc=
s-1.3=0A> =A0 =A0 =A0 =A0 =A0 =A0 Reporter:=0A> Alexander Kleymenov=0A> =A0=
 =A0 =A0 =A0 =A0 =A0 Assignee: Aaron=0A> Smuts=0A> =0A> =0A> The following =
groovy code demonstrates the problem: several=0A> threads write to the cach=
e and try to read previously=0A> written values. Sometimes values can be re=
trieved. In this=0A> case, subsequent tries can get the value, but not alwa=
ys.=0A> {code}=0A> cache =3D org.apache.jcs.JCS.getInstance("cache")=0A> gr=
oup =3D "group"=0A> worker =3D {=0A> =A0 =A0 def name =3D Thread.currentThr=
ead().name=0A> =A0 =A0 10000.times { idx ->=0A> =A0 =A0 =A0 =A0 if (idx) {=
=0A> =A0 =A0 =A0 =A0 =A0 =A0 // get previously=0A> stored value=0A> =A0 =A0=
 =A0 =A0 =A0 =A0 def res =3D=0A> cache.getFromGroup(idx-1, group)=0A> =A0 =
=A0 =A0 =A0 =A0 =A0 if (!res) {=0A> =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 //=0A> =
null value got inspite of the fact it was placed in cache!=0A> =A0 =A0 =A0 =
=A0 =A0 =A0 =A0 =A0=0A> println "ERROR: for ${idx} in " + name=0A> =A0 =A0 =
=A0 =A0 =A0 =A0 =A0 =A0 //=0A> try to get the value again:=0A> =A0 =A0 =A0 =
=A0 =A0 =A0 =A0 =A0 def=0A> n =3D 5=0A> =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0=0A>=
 while (n-- > 0) {=0A> =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0=0A> =A0 =A0 res =3D =
cache.getFromGroup(idx-1, group)=0A> =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0=0A> =
=A0 =A0 if (res) {=0A> =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0=0A> =A0 =A0 =A0 =A0 =
// the value finally appeared in=0A> cache=0A> =A0 =A0 =A0 =A0 =A0 =A0 =A0 =
=A0=0A> =A0 =A0 =A0 =A0 println "ERROR FIXED for ${idx}:=0A> ${res} " + nam=
e=0A> =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0=0A> =A0 =A0 =A0 =A0 break=0A> =A0 =A0=
 =A0 =A0 =A0 =A0 =A0 =A0=0A> =A0 =A0 }=0A> =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0=
=0A> =A0 =A0 println "ERROR STILL PERSISTS for ${idx} in "=0A> + name=0A> =
=A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0=0A> =A0 =A0 Thread.sleep(1000)=0A> =A0 =A0 =
=A0 =A0 =A0 =A0 =A0 =A0 }=0A> =A0 =A0 =A0 =A0 =A0 =A0 }=0A> =A0 =A0 =A0 =A0=
 }=0A> =A0 =A0 =A0 =A0 // put value in the cache=0A> =A0 =A0 =A0 =A0 cache.=
putInGroup(idx, group,=0A> [value:[a:1, b:2, c:3], aux:[1:'a', 2:'b', 3:'c'=
, t:name]])=0A> =A0 =A0 =A0 =A0 if (!(idx % 10000)) {=0A> =A0 =A0 =A0 =A0 =
=A0 =A0 println name+"=0A> "+idx=0A> =A0 =A0 =A0 =A0 }=0A> =A0 =A0 }=0A> }=
=0A> =0A> Thread.start worker=0A> Thread.start worker=0A> Thread.start work=
er=0A> Thread.start worker=0A> Thread.start worker=0A> Thread.start worker=
=0A> Thread.start worker=0A> Thread.start worker=0A> {code}=0A> =0A> Cache =
configuration:=0A> {code}=0A> jcs.default=3DCACHE=0A> jcs.default.cacheattr=
ibutes=3Dorg.apache.jcs.engine.CompositeCacheAttributes=0A> jcs.default.cac=
heattributes.MaxObjects=3D-1=0A> jcs.default.cacheattributes.MemoryCacheNam=
e=3Dorg.apache.jcs.engine.memory.lru.LRUMemoryCache=0A> jcs.default.cacheat=
tributes.DiskUsagePatternName=3DUPDATE=0A> jcs.default.cacheattributes.UseM=
emoryShrinker=3Dtrue=0A> jcs.default.cacheattributes.MaxMemoryIdleTimeSecon=
ds=3D10=0A> jcs.default.cacheattributes.ShrinkerIntervalSeconds=3D10=0A> jc=
s.default.elementattributes=3Dorg.apache.jcs.engine.ElementAttributes=0A> j=
cs.default.elementattributes.IsRemote=3Dfalse=0A> jcs.default.elementattrib=
utes.IsLateral=3Dfalse=0A> jcs.default.elementattributes.IsSpool=3Dtrue=0A>=
 jcs.default.elementattributes.IsEternal=3Dtrue=0A> =0A> jcs.auxiliary.CACH=
E=3Dorg.apache.jcs.auxiliary.disk.indexed.IndexedDiskCacheFactory=0A> jcs.a=
uxiliary.CACHE.attributes=3Dorg.apache.jcs.auxiliary.disk.indexed.IndexedDi=
skCacheAttributes=0A> jcs.auxiliary.CACHE.attributes.DiskPath=3D./cache=0A>=
 jcs.auxiliary.CACHE.attributes.MaxPurgatorySize=3D-1=0A> jcs.auxiliary.CAC=
HE.attributes.MaxKeySize=3D-1=0A> jcs.auxiliary.CACHE.attributes.MaxRecycle=
BinSize=3D500=0A> jcs.auxiliary.CACHE.attributes.ShutdownSpoolTimeLimit=3D6=
0=0A> jcs.auxiliary.CACHE.attributes.OptimizeAtRemoveCount=3D30000=0A> jcs.=
auxiliary.CACHE.attributes.OptimizeOnShutdown=3Dtrue=0A> jcs.auxiliary.CACH=
E.attributes.EventQueueType=3DSINGLE=0A> {code}=0A> =0A> -- =0A> This messa=
ge is automatically generated by JIRA.=0A> -=0A> If you think it was sent i=
ncorrectly contact one of the=0A> administrators: https://issues.apache.org=
/jira/secure/Administrators.jspa=0A> -=0A> For more information on JIRA, se=
e: http://www.atlassian.com/software/jira=0A> =0A> =A0 =A0 =A0 =A0 =0A> =0A=
> ---------------------------------------------------------------------=0A>=
 To unsubscribe, e-mail: [email protected]=0A> For add=
itional commands, e-mail: [email protected]=0A> =0A>