cassandra-commits mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Jonathan Ellis (JIRA)" <>
Subject [jira] [Updated] (CASSANDRA-2401) getColumnFamily() return null, which is not checked in scan() method, causing Timeout Exception in query
Date Wed, 04 May 2011 17:48:03 GMT


Jonathan Ellis updated CASSANDRA-2401:

    Attachment: 2401.txt

I found *a* bug that could cause this: Cassandra will re-create a deleted index entry if it
gets a write with an obsolete timestamp, but the data row tombstone will correctly suppress
an update there.

I don't think this is the bug Tey Kar is hitting, though, because unless I'm mistaken you
won't get this NPE until after the data row tombstone is removed by compaction after gc_grace_seconds.
 4 days isn't enough to see that unless you've tweaked gc_g_s.

Still, it's worth fixing.  Patch attached.  (Also adds an assert w/ more information if/when
another way of triggering this is found.)

> getColumnFamily() return null, which is not checked in scan()
method, causing Timeout Exception in query
> -------------------------------------------------------------------------------------------------------------------------------
>                 Key: CASSANDRA-2401
>                 URL:
>             Project: Cassandra
>          Issue Type: Bug
>          Components: Core
>    Affects Versions: 0.7.0
>         Environment: Hector 0.7.0-28, Cassandra 0.7.4, Windows 7, Eclipse
>            Reporter: Tey Kar Shiang
>            Assignee: Jonathan Ellis
>             Fix For: 0.7.6
>         Attachments: 2401.txt
>, line near 1680, "ColumnFamily data = getColumnFamily(new QueryFilter(dk,
path, firstFilter))", the data is returned null, causing NULL exception in "satisfies(data,
clause, primary)" which is not captured. The callback got timeout and return a Timeout exception
to Hector.
> The data is empty, as I traced, I have the the columns Count as 0 in removeDeletedCF(),
which return the null there. (I am new and trying to understand the logics around still).
Instead of crash to NULL, could we bypass the data?
> About my test:
> A stress-test program to add, modify and delete data to keyspace. I have 30 threads simulate
concurrent users to perform the actions above, and do a query to all rows periodically. I
have Column Family with rows (as File) and columns as index (e.g. userID, fileType).
> No issue on the first day of test, and stopped for 3 days. I restart the test on 4th
day, 1 of the users failed to query the files (timeout exception received). Most of the users
are still okay with the query.

This message is automatically generated by JIRA.
For more information on JIRA, see:

View raw message