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From Jonathan Ellis <jbel...@gmail.com>
Subject Re: frequent "unknown result" errors
Date Mon, 12 Apr 2010 15:30:29 GMT
Then you're probably using a client incompatible with the server
version you're using.

On Mon, Apr 12, 2010 at 10:24 AM, Lee Parker <lee@socialagency.com> wrote:
> If the connections are being made by individual PHP processes running from
> the command line, they shouldn't be using the same connection.  Should my
> code close the connections after each query and open a new one?
> Here is the flow of what is happening when we get the error:
> 1. Get a set of items from remote API
> 2. Insert all of the items into the items CF. (usually anywhere from 2 - 200
> items)
> 3. Query the correct index for all entries within a particular time frame
> (which is determined by the timeframe of the results of step 1)
> 4. Compare keys in index to keys of items inserted in step 2.
> 5. Insert new index columns for items which aren't already in the index.
> I am getting the "unknown result" error during step 3.
> Lee
>
> On Mon, Apr 12, 2010 at 10:05 AM, Jonathan Ellis <jbellis@gmail.com> wrote:
>>
>> unknown result means thrift is badly confused.  You will get this when
>> using the same thrift connection from multiple threads, for instance.
>>
>> On Mon, Apr 12, 2010 at 10:02 AM, Lee Parker <lee@socialagency.com> wrote:
>> > I am a newbie with Cassandra.  We are currently migrating a large amount
>> > of
>> > data out of MySQL into Cassandra.  I have two ColumnFamilies.  One
>> > contains
>> > one row per item and each item has roughly 12 columns.  These are items
>> > from
>> > REST APIs like the Twitter API.  Then I have a second ColumnFamily with
>> > very
>> > large rows and TimeUUID column names which contain the key of the items
>> > in
>> > the other ColumnFamily.  So one ColumnFamily has lots of rows with a low
>> > number of columns per row, and the other has relatively few rows with a
>> > large (~500k) columns per row.
>> > I am getting rather frequent errors with "unknown result" from get_slice
>> > and
>> > multiget_slice calls from the index ColumnFamily.  I am using Pandra for
>> > the
>> > calls.  I can see that this is a generic exception thrown by the
>> > Cassandra
>> > Thrift package when it doesn't know what else to say.  Is there a way to
>> > actually see what the result was in a more raw form from the Thrift
>> > protocol?
>> > One thought I had on why this is happening is that my results might be
>> > larger than the configuration settings.  Does anyone have any good ideas
>> > on
>> > how to calculate what the ideal values of SlicedBufferSizeInKB
>> > and ColumnIndexSizeInKB should be?  If these are too low, would i get a
>> > more
>> > descriptive error?
>> > Lee Parker
>
>

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