incubator-cassandra-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Michael Pearson <mjpear...@gmail.com>
Subject Re: frequent "unknown result" errors
Date Fri, 16 Apr 2010 02:42:08 GMT
Lee, I dropped (official) 0.5 support from Pandra yesterday and
committed 0.6 Thrift files, if you're still considering that
upgrade... worth a shot imo.

-michael

On Tue, Apr 13, 2010 at 7:19 AM, Lee Parker <lee@socialagency.com> wrote:
> So, it didn't get rid of the problem, i'm still getting the errors.  The
> only thing I can think of now is top upgrade to 0.6, but I would prefer to
> stay with the current stable release.  I have regenerated the thrift code
> for 0.5.0 and there is no difference between those files and the ones i'm
> using in my software now.  Are there any other suggestions?  What code would
> be helpful to see?
> Lee
>
> On Mon, Apr 12, 2010 at 1:17 PM, Keith Thornhill <keith@raptr.com> wrote:
>>
>> i also noticed "unknown result" errors when my php thrift code was
>> generated using a different version of thrift than cassandra uses.
>>
>> after regenerating my php code from thrift-r917130 (for
>> cassandra-0.6.0-rc1), the errors stopped.
>>
>> -keith
>>
>> On Mon, Apr 12, 2010 at 9:40 AM, vineet daniel <vineetdaniel@gmail.com>
>> wrote:
>> > 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
>> >>> >> >
>> >>> >> >
>> >>> >
>> >>> >
>> >>
>> >
>> >
>
>



-- 
http://www.x0rz.com
http://www.linkedin.com/in/mjpearson

Mime
View raw message