JNI ERROR (app bug): local reference table overflow (max=512) while executing Couchbae Lite Query

[konbernu]

I have a problem while i m executing a Couchbase Lite Query.

I m doing the following:

row_enumerator = request_query.run()
while row_enumerator.hasNext():
	row=row_enumerator.next()
	row_id=row.getDocumentId()
        row_key_raw = row.getKey()
        etc....

The Class of row is Couchbase QueryRow.

In each loop I transform the row value (HashMap/Map/ArrayList/LazyArrayList) to json string with jackson-databind.

This error comes in the while loop:

02-06 15:57:04.933 30996-31045/org.example.myapp A/art: art/runtime/indirect_reference_table.cc:115] JNI ERROR (app bug): local reference table overflow (max=512)
02-06 15:57:04.933 30996-31045/org.example.myapp A/art: art/runtime/indirect_reference_table.cc:115] local reference table dump:
02-06 15:57:04.933 30996-31045/org.example.myapp A/art: art/runtime/indirect_reference_table.cc:115]   Last 10 entries (of 512):
02-06 15:57:04.933 30996-31045/org.example.myapp A/art: art/runtime/indirect_reference_table.cc:115]       511: 0x7162ae98 java.lang.Class<java.lang.Class>
02-06 15:57:04.933 30996-31045/org.example.myapp A/art: art/runtime/indirect_reference_table.cc:115]       510: 0x1311ff10 java.lang.Class<com.couchbase.lite.QueryRow>
02-06 15:57:04.933 30996-31045/org.example.myapp A/art: art/runtime/indirect_reference_table.cc:115]       509: 0x7164dbb0 java.lang.Class<java.lang.Integer>
02-06 15:57:04.933 30996-31045/org.example.myapp A/art: art/runtime/indirect_reference_table.cc:115]       508: 0x7164dbb0 java.lang.Class<java.lang.Integer>
02-06 15:57:04.933 30996-31045/org.example.myapp A/art: art/runtime/indirect_reference_table.cc:115]       507: 0x7164dbb0 java.lang.Class<java.lang.Integer>
02-06 15:57:04.933 30996-31045/org.example.myapp A/art: art/runtime/indirect_reference_table.cc:115]       506: 0x7164dbb0 java.lang.Class<java.lang.Integer>
02-06 15:57:04.933 30996-31045/org.example.myapp A/art: art/runtime/indirect_reference_table.cc:115]       505: 0x7164dbb0 java.lang.Class<java.lang.Integer>
02-06 15:57:04.933 30996-31045/org.example.myapp A/art: art/runtime/indirect_reference_table.cc:115]       504: 0x7164dbb0 java.lang.Class<java.lang.Integer>
02-06 15:57:04.933 30996-31045/org.example.myapp A/art: art/runtime/indirect_reference_table.cc:115]       503: 0x7164dbb0 java.lang.Class<java.lang.Integer>
02-06 15:57:04.933 30996-31045/org.example.myapp A/art: art/runtime/indirect_reference_table.cc:115]       502: 0x7164dbb0 java.lang.Class<java.lang.Integer>
02-06 15:57:04.933 30996-31045/org.example.myapp A/art: art/runtime/indirect_reference_table.cc:115]   Summary:
02-06 15:57:04.943 30996-31045/org.example.myapp A/art: art/runtime/indirect_reference_table.cc:115]         1 of com.couchbase.lite.QueryRow
02-06 15:57:04.943 30996-31045/org.example.myapp A/art: art/runtime/indirect_reference_table.cc:115]       510 of java.lang.Class (56 unique instances)
02-06 15:57:04.943 30996-31045/org.example.myapp A/art: art/runtime/indirect_reference_table.cc:115]         1 of java.lang.Thread
02-06 15:57:04.943 30996-31045/org.example.myapp A/art: art/runtime/indirect_reference_table.cc:115] 
02-06 15:57:05.233 30996-31002/org.example.myapp W/art: Suspending all threads took: 296.012ms
02-06 15:57:05.263 30996-31045/org.example.myapp A/art: art/runtime/barrier.cc:90] Check failed: count_ == 0 (count_=-1, 0=0) Attempted to destroy barrier with non zero count
02-06 15:57:05.263 30996-31045/org.example.myapp A/art: art/runtime/runtime.cc:366] Runtime aborting --- recursively, so no thread-specific detail!
02-06 15:57:05.263 30996-31045/org.example.myapp A/art: art/runtime/runtime.cc:366] 
02-06 15:57:05.693 30996-31045/org.example.myapp W/google-breakpad: ### ### ### ### ### ### ### ### ### ### ### ### ###
02-06 15:57:05.693 30996-31045/org.example.myapp W/google-breakpad: Chrome build fingerprint:
02-06 15:57:05.693 30996-31045/org.example.myapp W/google-breakpad: 147.5
02-06 15:57:05.693 30996-31045/org.example.myapp W/google-breakpad: 14705
02-06 15:57:05.693 30996-31045/org.example.myapp W/google-breakpad: ### ### ### ### ### ### ### ### ### ### ### ### ###
02-06 15:57:05.693 30996-31045/org.example.myapp A/libc: Fatal signal 6 (SIGABRT), code -6 in tid 31045 (PythonThread)

[inclement]

I think you're hitting the hard limit on the number of JNI references, which unfortunately we can't control. There's some discussion for how to work around this in various places - I found http://stackoverflow.com/a/20918022/2469283 which looks potentially useful.

Unfortunately this is a limitation of JNI and not something we can change, so I'm going to close this issue. It might be worth opening one about the problem in the Pyjnius repo though - even if we can't fix it in general, it might generate some useful discussion or at least an addition to the pyjnius docs about the problem.

[konbernu]

I am sorry, i forgot to mention that I can run the Query multiple times correcty, before it crashes down. So the issue is probably in https://github.com/kivy/pyjnius/blob/master/jnius/jnius_conversion.pxi .