Re: NullPointerException while create region during server restart

[Kirk Lund]

Hi Mario,

I would guess that *getPdxRegistry()* is returning a null until after the
registry has finished initializing. Just a guess though.

Here's a spreadsheet
a
couple of us created and used as a reference for some work about a year and
a half ago. The source code line numbers probably aren't correct anymore,
but the order of steps and general details should still be accurate. As
you'll see, the PDX region (aka the PDX registry) is created at step 19 of
the spreadsheet.

Step 26 is the creation of the CacheServerMXBean.
Step 29 marks 'Online' status change.

You need to wait for all servers to reach 'Online' on Step 29 of the
spreadsheet before making any changes like creating regions.

To understand how to identify 'Online', take a look at these two acceptance
tests:
1.
geode-assembly/src/acceptanceTest/java/org/apache/geode/launcher/ServerStartupOnlineTest.java
2.
geode-assembly/src/acceptanceTest/java/org/apache/geode/launcher/ServerStartupNotificationTest.java

-Kirk

On Tue, Jul 6, 2021 at 12:06 AM Mario Kevo  wrote:

> Hi Geode devs,
>
> I opened a new ticket https://issues.apache.org/jira/browse/GEODE-9409
> regarding NullPointerException on creating region while one of the servers
> is restarting.
> If we run the "create region" command through gfsh while the server is
> starting it passed, but if the server is restarted then it fails. The
> difference is that when we restarted the server, we kill them and start
> again. As it has already a server directory, it takes more time to get the
> server up as expected.
> In that case, if we run the "create region" command it can happen that the
> cache is not fully created and we are trying to do something on that. That
> can lead to the NullPointerException, as creating region catches
> pdxRegistry from the cache while doing findDiskStore, but sometimes it is
> not initialized in the cache yet. So every method run against that will
> throw NullPoniterException.
> There is a part of the code where the exception is thrown:
>
> DiskStoreImpl findDiskStore(RegionAttributes regionAttributes,
> InternalRegionArguments internalRegionArgs) {
>   // validate that persistent type registry is persistent
>   if (getAttributes().getDataPolicy().withPersistence()) {
> getCache().getPdxRegistry().creatingPersistentRegion();
>   }
>
> As I already mention, getPdxRegistry(LocalRegion.java) will be null if it
> is not yet initialized in create(CacheCreation.java):
>
> DiskStoreAttributesCreation pdxRegDSC = initializePdxDiskStore(cache);
>
> cache.initializePdxRegistry();
>
> createDiskStores(cache, pdxRegDSC);
>
> I tried to do some fixes, but without a success. 
> It can be passed if we add some retry and sleep, but that is not
> acceptable.
>
> So if someone has some idea how to do some wait until pdxRegistry is
> initialized or something else what will help us to avoid this problem?
>
> BR,
> Mario
>

Re: NullPointerException while create region during server restart

[Anthony Baker]

When the NPE occurs, has the server completed its bootstrapping from cluster 
configuration yet?

Anthony


> On Jul 6, 2021, at 12:06 AM, Mario Kevo  wrote:
> 
> Hi Geode devs,
> 
> I opened a new ticket https://issues.apache.org/jira/browse/GEODE-9409 
> regarding NullPointerException on creating region while one of the servers is 
> restarting.
> If we run the "create region" command through gfsh while the server is 
> starting it passed, but if the server is restarted then it fails. The 
> difference is that when we restarted the server, we kill them and start 
> again. As it has already a server directory, it takes more time to get the 
> server up as expected.
> In that case, if we run the "create region" command it can happen that the 
> cache is not fully created and we are trying to do something on that. That 
> can lead to the NullPointerException, as creating region catches pdxRegistry 
> from the cache while doing findDiskStore, but sometimes it is not initialized 
> in the cache yet. So every method run against that will throw 
> NullPoniterException.
> There is a part of the code where the exception is thrown:
> 
> DiskStoreImpl findDiskStore(RegionAttributes regionAttributes,
>InternalRegionArguments internalRegionArgs) {
>  // validate that persistent type registry is persistent
>  if (getAttributes().getDataPolicy().withPersistence()) {
>getCache().getPdxRegistry().creatingPersistentRegion();
>  }
> 
> As I already mention, getPdxRegistry(LocalRegion.java) will be null if it is 
> not yet initialized in create(CacheCreation.java):
> 
> DiskStoreAttributesCreation pdxRegDSC = initializePdxDiskStore(cache);
> 
> cache.initializePdxRegistry();
> 
> createDiskStores(cache, pdxRegDSC);
> 
> I tried to do some fixes, but without a success. 
> It can be passed if we add some retry and sleep, but that is not acceptable.
> 
> So if someone has some idea how to do some wait until pdxRegistry is 
> initialized or something else what will help us to avoid this problem?
> 
> BR,
> Mario