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From vineet daniel <vineetdan...@gmail.com>
Subject Re: frequent "unknown result" errors
Date Mon, 12 Apr 2010 16:40:24 GMT
can you post the code

On Mon, Apr 12, 2010 at 9:22 PM, Lee Parker <lee@socialagency.com> wrote:

> According to his docs, he says you need Cassandra >= 0.5.0.  I guess it is
> possible that the included thrift files are targeted at 0.6, but I don't see
> the "batch_mutate" method which is part of 0.6.  So I'm assuming that it
> should work fine with 0.5.0.
>
> I have now changed some of those entries in the configs and I have not seen
> the error in a while.  So, it may have simply been that I was trying to do a
> query which was too large for the configured buffer to handle.
>
> For the time being, I would like to stick with 0.5 as it is the "stable"
> release and we are running this in a production environment.
>
> Lee Parker
>
> On Mon, Apr 12, 2010 at 10:45 AM, Jonathan Ellis <jbellis@gmail.com>wrote:
>
>> Pandra is probably targetting 0.6.
>>
>> If you're just starting, there's no reason for you not to use 0.6 over 0.5
>> now.
>>
>> On Mon, Apr 12, 2010 at 10:42 AM, Lee Parker <lee@socialagency.com>
>> wrote:
>> > I'm using the thrift client which is packaged with Pandra and my
>> cassandra
>> > version is 0.5.0 which is in the debian packages.  How can i tell which
>> > version of Thrift i'm using?
>> > Lee
>> >
>> > On Mon, Apr 12, 2010 at 10:30 AM, Jonathan Ellis <jbellis@gmail.com>
>> wrote:
>> >>
>> >> 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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