You are viewing a plain text version of this content. The canonical link for it is here.
Posted to user@cassandra.apache.org by Joel Samuelsson <sa...@gmail.com> on 2014/03/07 15:22:03 UTC
Weird timeouts
I try to fetch all the row keys from a column family (there should only be
a couple of hundred in that CF) in several different ways but I get
timeouts whichever way I try:
Through the cassandra cli:
Fetching 45 rows is fine:
list cf limit 46 columns 0;
.
.
.
45 Rows Returned.
Elapsed time: 298 msec(s).
Fetching 46 rows however gives me a timeout after a minute or so:
list cf limit 46 columns 0;
null
TimedOutException()...
Through pycassa:
keys = cf.get_range(column_count = 1, buffer_size = 2)
for key, val in keys:
print key
This prints some keys and then gets stuck at the same place each time and
then timeouts.
The columns (column names + value) in the rows should be less than 100
bytes each, though there may be a lot of them on a particular row.
To me it seems like one of the rows take too long time to fetch but I don't
know why since I am limitiing the number of columns to 0. Without seeing
the row, I have a hard time knowing what could be wrong. Do you have any
ideas?
Re: Weird timeouts
Posted by Ken Hancock <ke...@schange.com>.
Are you on Cassandra 1.2 and can utilize the trace functionality? Might be
an informative route.
Ken
On Fri, Mar 7, 2014 at 9:22 AM, Joel Samuelsson
<sa...@gmail.com>wrote:
> I try to fetch all the row keys from a column family (there should only be
> a couple of hundred in that CF) in several different ways but I get
> timeouts whichever way I try:
>
> Through the cassandra cli:
> Fetching 45 rows is fine:
> list cf limit 46 columns 0;
> .
> .
> .
> 45 Rows Returned.
> Elapsed time: 298 msec(s).
>
> Fetching 46 rows however gives me a timeout after a minute or so:
> list cf limit 46 columns 0;
> null
> TimedOutException()...
>
> Through pycassa:
> keys = cf.get_range(column_count = 1, buffer_size = 2)
>
> for key, val in keys:
> print key
>
> This prints some keys and then gets stuck at the same place each time and
> then timeouts.
>
> The columns (column names + value) in the rows should be less than 100
> bytes each, though there may be a lot of them on a particular row.
>
> To me it seems like one of the rows take too long time to fetch but I
> don't know why since I am limitiing the number of columns to 0. Without
> seeing the row, I have a hard time knowing what could be wrong. Do you have
> any ideas?
>
>
>
--
*Ken Hancock *| System Architect, Advanced Advertising
SeaChange International
50 Nagog Park
Acton, Massachusetts 01720
ken.hancock@schange.com | www.schange.com |
NASDAQ:SEAC<http://www.schange.com/en-US/Company/InvestorRelations.aspx>
Office: +1 (978) 889-3329 | [image: Google Talk:]
ken.hancock@schange.com | [image:
Skype:]hancockks | [image: Yahoo IM:]hancockks [image:
LinkedIn]<http://www.linkedin.com/in/kenhancock>
[image: SeaChange International]
<http://www.schange.com/>This e-mail and any attachments may contain
information which is SeaChange International confidential. The information
enclosed is intended only for the addressees herein and may not be copied
or forwarded without permission from SeaChange International.
Re: Weird timeouts
Posted by Joel Samuelsson <sa...@gmail.com>.
I am on Cassandra 2.0.5. How can I use the trace functionality?
I did not check for exceptions. I will rerun and check.
Thanks for suggestions.
/Joel
2014-03-07 17:54 GMT+01:00 Duncan Sands <du...@gmail.com>:
> Hi Joel,
>
>
> On 07/03/14 15:22, Joel Samuelsson wrote:
>
>> I try to fetch all the row keys from a column family (there should only
>> be a
>> couple of hundred in that CF) in several different ways but I get timeouts
>> whichever way I try:
>>
>
> did you check the node logs for exceptions? You can get this kind of
> thing if there is an assertion failure when reading a particular row due to
> corruption for example.
>
> Ciao, Duncan.
>
>
>
>> Through the cassandra cli:
>> Fetching 45 rows is fine:
>> list cf limit 46 columns 0;
>> .
>> .
>> .
>> 45 Rows Returned.
>> Elapsed time: 298 msec(s).
>>
>> Fetching 46 rows however gives me a timeout after a minute or so:
>> list cf limit 46 columns 0;
>> null
>> TimedOutException()...
>>
>> Through pycassa:
>> keys = cf.get_range(column_count = 1, buffer_size = 2)
>>
>> for key, val in keys:
>> print key
>>
>> This prints some keys and then gets stuck at the same place each time and
>> then
>> timeouts.
>>
>> The columns (column names + value) in the rows should be less than 100
>> bytes
>> each, though there may be a lot of them on a particular row.
>>
>> To me it seems like one of the rows take too long time to fetch but I
>> don't know
>> why since I am limitiing the number of columns to 0. Without seeing the
>> row, I
>> have a hard time knowing what could be wrong. Do you have any ideas?
>>
>>
>>
>
Re: Weird timeouts
Posted by Duncan Sands <du...@gmail.com>.
Hi Joel,
On 07/03/14 15:22, Joel Samuelsson wrote:
> I try to fetch all the row keys from a column family (there should only be a
> couple of hundred in that CF) in several different ways but I get timeouts
> whichever way I try:
did you check the node logs for exceptions? You can get this kind of thing if
there is an assertion failure when reading a particular row due to corruption
for example.
Ciao, Duncan.
>
> Through the cassandra cli:
> Fetching 45 rows is fine:
> list cf limit 46 columns 0;
> .
> .
> .
> 45 Rows Returned.
> Elapsed time: 298 msec(s).
>
> Fetching 46 rows however gives me a timeout after a minute or so:
> list cf limit 46 columns 0;
> null
> TimedOutException()...
>
> Through pycassa:
> keys = cf.get_range(column_count = 1, buffer_size = 2)
>
> for key, val in keys:
> print key
>
> This prints some keys and then gets stuck at the same place each time and then
> timeouts.
>
> The columns (column names + value) in the rows should be less than 100 bytes
> each, though there may be a lot of them on a particular row.
>
> To me it seems like one of the rows take too long time to fetch but I don't know
> why since I am limitiing the number of columns to 0. Without seeing the row, I
> have a hard time knowing what could be wrong. Do you have any ideas?
>
>