Re: Query timed out after PT1M

2021-04-13 Thread Bowen Song

Ouch, counters.

Counters in Cassandra have pretty bad performance comparing to 
everything else in Cassandra or counters (and their equivalent, such as 
integer types) in other mainstream databases, and they often are 
inaccurate too. I personally would recommend against the use of counters 
in Cassandra. You may need to add more nodes to deal with the peak load 
in order to avoid the timeouts if you can't move away from using 
counters in Cassandra.



On 13/04/2021 17:45, Joe Obernberger wrote:


Thank you Bowen - I wasn't familiar with PT1M.
I'm doing the following:

update doc.seq set doccount=doccount+? where id=?
Which runs OK.
Immediately following the update, I do:
select doccount from doc.seq where id=?
It is the above statement that is throwing the error under heavy load.

The select also frequently fails with a "No node was available to 
execute the query".  I wait 50mSec and retry and that typically 
works.  Sometimes it will retry as many as 15 times before getting a 
response, but this PT1M error is new.


Running: nodetool cfstats doc.seq results in:

Total number of tables: 80

Keyspace : doc
    Read Count: 57965255
    Read Latency: 0.3294544486347899 ms
    Write Count: 384658145
    Write Latency: 0.1954830251859089 ms
    Pending Flushes: 0
    Table: seq
    SSTable count: 9
    Space used (live): 48344
    Space used (total): 48344
    Space used by snapshots (total): 0
    Off heap memory used (total): 376
    SSTable Compression Ratio: 0.6227272727272727
    Number of partitions (estimate): 35
    Memtable cell count: 6517
    Memtable data size: 264
    Memtable off heap memory used: 0
    Memtable switch count: 154
    Local read count: 12900131
    Local read latency: NaN ms
    Local write count: 15981389
    Local write latency: NaN ms
    Pending flushes: 0
    Percent repaired: 10.69
    Bloom filter false positives: 0
    Bloom filter false ratio: 0.0
    Bloom filter space used: 168
    Bloom filter off heap memory used: 96
    Index summary off heap memory used: 168
    Compression metadata off heap memory used: 112
    Compacted partition minimum bytes: 125
    Compacted partition maximum bytes: 149
    Compacted partition mean bytes: 149
    Average live cells per slice (last five minutes): NaN
    Maximum live cells per slice (last five minutes): 0
    Average tombstones per slice (last five minutes): NaN
    Maximum tombstones per slice (last five minutes): 0
    Dropped Mutations: 0

-Joe

On 4/13/2021 12:35 PM, Bowen Song wrote:


The error message is clear, it was a DriverTimeoutException, and it 
was because the query timed out after one minute.


/Note: "PT1M" means a period of one minute, see 
//https://en.wikipedia.org/wiki/ISO_8601#Durations 
/


If you need help from us to find out why did it happen, you will need 
to share a bit more information with us, such as the CQL query and 
the table definition.



On 13/04/2021 16:53, Joe Obernberger wrote:

I'm getting this error:
com.datastax.oss.driver.api.core.DriverTimeoutException: Query timed 
out after PT1M


but I can't find any documentation on this message.  Anyone know 
what this means?  I'm updating a counter value and then doing a 
select from the table.  The table that I'm selecting from is very 
small <100 rows.


Thank you!

-Joe




 
	Virus-free. www.avg.com 
 



<#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>


Re: Query timed out after PT1M

2021-04-13 Thread Joe Obernberger
Interestingly, I just tried creating two CqlSession objects and when I 
use both instead of a single CqlSession for all queries, the 'No Node 
available to execute query' no longer happens.  In other words, if I 
use a different CqlSession for updating the doc.seq table, it works.  
If that session is shared with other queries, I get the errors.


-Joe

On 4/13/2021 12:35 PM, Bowen Song wrote:


The error message is clear, it was a DriverTimeoutException, and it 
was because the query timed out after one minute.


/Note: "PT1M" means a period of one minute, see 
//https://en.wikipedia.org/wiki/ISO_8601#Durations 
/


If you need help from us to find out why did it happen, you will need 
to share a bit more information with us, such as the CQL query and the 
table definition.



On 13/04/2021 16:53, Joe Obernberger wrote:

I'm getting this error:
com.datastax.oss.driver.api.core.DriverTimeoutException: Query timed 
out after PT1M


but I can't find any documentation on this message.  Anyone know 
what this means?  I'm updating a counter value and then doing a 
select from the table.  The table that I'm selecting from is very 
small <100 rows.


Thank you!

-Joe




 
	Virus-free. www.avg.com 
 



<#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>

Re: Query timed out after PT1M

2021-04-13 Thread Joe Obernberger

Thank you Bowen - I wasn't familiar with PT1M.
I'm doing the following:

update doc.seq set doccount=doccount+? where id=?
Which runs OK.
Immediately following the update, I do:
select doccount from doc.seq where id=?
It is the above statement that is throwing the error under heavy load.

The select also frequently fails with a "No node was available to 
execute the query".  I wait 50mSec and retry and that typically 
works.  Sometimes it will retry as many as 15 times before getting a 
response, but this PT1M error is new.


Running: nodetool cfstats doc.seq results in:

Total number of tables: 80

Keyspace : doc
    Read Count: 57965255
    Read Latency: 0.3294544486347899 ms
    Write Count: 384658145
    Write Latency: 0.1954830251859089 ms
    Pending Flushes: 0
    Table: seq
    SSTable count: 9
    Space used (live): 48344
    Space used (total): 48344
    Space used by snapshots (total): 0
    Off heap memory used (total): 376
    SSTable Compression Ratio: 0.6227272727272727
    Number of partitions (estimate): 35
    Memtable cell count: 6517
    Memtable data size: 264
    Memtable off heap memory used: 0
    Memtable switch count: 154
    Local read count: 12900131
    Local read latency: NaN ms
    Local write count: 15981389
    Local write latency: NaN ms
    Pending flushes: 0
    Percent repaired: 10.69
    Bloom filter false positives: 0
    Bloom filter false ratio: 0.0
    Bloom filter space used: 168
    Bloom filter off heap memory used: 96
    Index summary off heap memory used: 168
    Compression metadata off heap memory 
used: 112

    Compacted partition minimum bytes: 125
    Compacted partition maximum bytes: 149
    Compacted partition mean bytes: 149
    Average live cells per slice (last five 
minutes): NaN
    Maximum live cells per slice (last five 
minutes): 0
    Average tombstones per slice (last five 
minutes): NaN
    Maximum tombstones per slice (last five 
minutes): 0

    Dropped Mutations: 0

-Joe

On 4/13/2021 12:35 PM, Bowen Song wrote:


The error message is clear, it was a DriverTimeoutException, and it 
was because the query timed out after one minute.


/Note: "PT1M" means a period of one minute, see 
//https://en.wikipedia.org/wiki/ISO_8601#Durations 
/


If you need help from us to find out why did it happen, you will need 
to share a bit more information with us, such as the CQL query and the 
table definition.



On 13/04/2021 16:53, Joe Obernberger wrote:

I'm getting this error:
com.datastax.oss.driver.api.core.DriverTimeoutException: Query timed 
out after PT1M


but I can't find any documentation on this message.  Anyone know 
what this means?  I'm updating a counter value and then doing a 
select from the table.  The table that I'm selecting from is very 
small <100 rows.


Thank you!

-Joe




 
	Virus-free. www.avg.com 
 



<#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>

Re: Query timed out after PT1M

2021-04-13 Thread Bowen Song
The error message is clear, it was a DriverTimeoutException, and it was 
because the query timed out after one minute.


/Note: "PT1M" means a period of one minute, see 
//https://en.wikipedia.org/wiki/ISO_8601#Durations 
/


If you need help from us to find out why did it happen, you will need to 
share a bit more information with us, such as the CQL query and the 
table definition.



On 13/04/2021 16:53, Joe Obernberger wrote:

I'm getting this error:
com.datastax.oss.driver.api.core.DriverTimeoutException: Query timed 
out after PT1M


but I can't find any documentation on this message.  Anyone know what 
this means?  I'm updating a counter value and then doing a select from 
the table.  The table that I'm selecting from is very small <100 rows.


Thank you!

-Joe