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Gmane
From: aaron morton <aaron <at> thelastpickle.com>
Subject: Re: Cassandra Compaction is Killing
Newsgroups: gmane.comp.db.cassandra.user
Date: Tuesday 7th February 2012 19:27:43 UTC (over 5 years ago)
> Is Cassandra logging messages about the the heap been full, what are they
saying ? 
They are saying http://khaaan.com/

You do not have enough memory allocated to the JVM to work efficiently,
that needs to be fixed. 

First step, disable all row and key caches until you get stable. 

> The size of memory is there a way to calculate the max required or I have
to hit and try.

The best approach is to let Cassandra take care of it. See the
conf/cassandra-env.sh . The maximum useful heap size is 8GB. 

> When you say memtable threshold is 0.75 do you mean the
memtable_total_space_in_mb setting in yaml ? 
> I am talking of : flush_largest_memtables_at: 0.75
That is a safety valve, the fact that is it trigger is a symptom of memory
issues. see http://thelastpickle.com/2011/05/04/How-are-Memtables-measured/

>   Are you talking of in_memory_compaction_limit_in_mb which is by default
1/3 of heap size. 
in_memory_compaction_limit defaults to 64MB and influences how much memory
compaction will use 
see https://github.com/apache/cassandra/blob/trunk/conf/cassandra.yaml#L334

> Is RF:7 increasing the pressure as well. But if I reduce it to say 4 I am
effectively putting the load to only 4 servers as Solandra writes all the
docs driven by a max_docs_per_shard_size (which is 1Million) to a single
shard (single physical node:-> it uses it own partitioner) and I have total
docs as 300K.


I do not know that much about solandra. 

I would do this:
* disable all the caches
* allocate more memory / let cassandra take care of it (you have a high
setting for the young gen).
* consider reducing the in_memory_compaction_limit

Cheers

-----------------
Aaron Morton
Freelance Developer
@aaronmorton
http://www.thelastpickle.com

On 7/02/2012, at 2:46 PM, shubham srivastava wrote:

> Hi Aaron,
> 
> Is Cassandra logging messages about the the heap been full, what are they
saying ? 
> 
> Most of the times but not always below logs are published by cassandra:
> 
>  WARN [ScheduledTasks:1] 2012-02-06 22:17:50,375 GCInspector.java (line
143) Heap is 0.784281626909687 full.  You may need to reduce memtable
and/or cache sizes.  Cassandra will now flush up to the two largest
memtables to free up memory.  Adjust flush_largest_memtables_at threshold
in cassandra.yaml if you don't want Cassandra to do this automatically
>  WARN [ScheduledTasks:1] 2012-02-06 22:17:50,376 StorageService.java
(line 2418) Flushing ColumnFamilyStore(table='LH',
columnFamily='SavedSearchRequest') to relieve memory pressure
>  INFO [ScheduledTasks:1] 2012-02-06 22:17:50,629 ColumnFamilyStore.java
(line 1128) Enqueuing flush of
[email protected](6964940/13461931 serialized/live
bytes, 5794 ops)
>  WARN [ScheduledTasks:1] 2012-02-06 22:17:51,242 StorageService.java
(line 2422) Flushing ColumnFamilyStore(table='LH',
columnFamily='BookedHotels') to relieve memory pressure
>  INFO [ScheduledTasks:1] 2012-02-06 22:17:51,242 ColumnFamilyStore.java
(line 1128) Enqueuing flush of [email protected](1575/1968
serialized/live bytes, 35 ops)
>  INFO [FlushWriter:5] 2012-02-06 22:17:51,244 Memtable.java (line 237)
Writing [email protected](6964940/13461931
serialized/live bytes, 5794 ops)
>  INFO [ScheduledTasks:1] 2012-02-06 22:18:03,144 GCInspector.java (line
122) GC for ConcurrentMarkSweep: 3783 ms for 2 collections, 2785603776
used; max is 6120341504
> 
> When you say memtable threshold is 0.75 do you mean the
memtable_total_space_in_mb setting in yaml ? 
> I am talking of : flush_largest_memtables_at: 0.75
> 
> Wide rows, such as the TL column family in the L keyspace can increase
the about of GC work that goes on. This can be somewhat alleviated by
reducing the in_memory_compaction_limit_in_mb , this will increase the
amount of IO that is needed. 
> 
>   Are you talking of in_memory_compaction_limit_in_mb which is by default
1/3 of heap size. 
> 
> 
> Heavy write traffic can also increase GC activity. Watch the tp stats
during the load process, are you overloading the cluster ? Do you see
pending tasks backing up ? 
> 
> Yes :Below are the same:
> #TpStats
> 
> Pool Name                    Active   Pending      Completed   Blocked 
All time blocked
> ReadStage                        32       922         159030         0   
             0
> RequestResponseStage              0         0           4563         0   
             0
> MutationStage                     0         0         249357         0   
             0
> ReadRepairStage                   0         0              3         0   
             0
> ReplicateOnWriteStage             0         0              0         0   
             0
> GossipStage                       0         0           4670         0   
             0
> AntiEntropyStage                  0         0              0         0   
             0
> MigrationStage                    0         0              0         0   
             0
> MemtablePostFlusher               0         0             19         0   
             0
> StreamStage                       0         0              0         0   
             0
> FlushWriter                       0         0             19         0   
             5
> MiscStage                         0         0              0         0   
             0
> FlushSorter                       0         0              0         0   
             0
> InternalResponseStage             0         0              0         0   
             0
> HintedHandoff                     0         0              8         0   
             0
> 
> Message type           Dropped
> RANGE_SLICE                  1
> READ_REPAIR                  0
> BINARY                       0
> READ                    147188
> MUTATION                     1
> REQUEST_RESPONSE           327 
> 
> 
> The size of memory is there a way to calculate the max required or I have
to hit and try.
> 
> Is RF:7 increasing the pressure as well. But if I reduce it to say 4 I am
effectively putting the load to only 4 servers as Solandra writes all the
docs driven by a max_docs_per_shard_size (which is 1Million) to a single
shard (single physical node:-> it uses it own partitioner) and I have total
docs as 300K.
> 
> Regards,
> Shubham
> 
> On Tue, Feb 7, 2012 at 12:51 AM, aaron morton 
wrote:
> Sounds like GC is the first problem to tackle. Can you give the process
more memory ?  
> 
> Look at the logs and work out what the GC is doing, the cassandra logs
are not exactly the same as this but you get the idea http://blogs.oracle.com/poonam/entry/understanding_cms_gc_logs
> 
> The next thing I normally do is revert all changes to the default memory
and GC settings. 
> 
> When you say memtable threshold is 0.75 do you mean the
memtable_total_space_in_mb setting in yaml ? 
> Is Cassandra logging messages about the the heap been full, what are they
saying ? 
> 
> Wide rows, such as the TL column family in the L keyspace can increase
the about of GC work that goes on. This can be somewhat alleviated by
reducing the in_memory_compaction_limit_in_mb , this will increase the
amount of IO that is needed. 
> 
>   Are you talking of in_memory_compaction_limit_in_mb which is by default
1/3 of heap size. 
> 
> 
> Cheers
> 
> -----------------
> Aaron Morton
> Freelance Developer
> @aaronmorton
> http://www.thelastpickle.com
> 
> On 4/02/2012, at 5:58 PM, Shubham Srivastava wrote:
> 
>> I have a cassandra setup with 7 Node Ring single DC with RF:7 and
Read:CL:1.There is live traffic on these nodes except one -> the traffic is
90% read. There are also writes happening to all these nodes which
typically are user specific data etc.These nodes aNow at times what is
happening is there are 2-3 say nodes getting in a hanged state and
eventually the whole ring behaves so. There state in terms of CPU Usage is
very High 17Loads ,network incoming and outgoing requests packet were very
high and there is continuous GC(Major and Minor) pauses happening and Read
Messages dropped  simultaneously.Also the SSTables couunt have increased
and decreased for some families during this time. So majorly its the GC and
SStable compaction and Memtable flush happening. We are running cassandra
behind solr using Solandra.The max docs that we have are around 0.5Million.
>> 
>> We keep one node as the main write node where we run sheduled job thats
pools data into the cluster from MySql db.These jobs are run
hourly.Recently we have increased the data to somewhere to the size of 30X
. Before the same setup was stable and these jobs used to run in every 5
minutes apart from the similar problem 2-3 times.
>> 
>> GC:Settings
>> 4Gb Heap Xmx,Xms
>> 2Gb Young Geneartion: Xmn
>> ParNew
>> CMS
>> -XX:+UseParNewGC" 
>> -XX:+UseConcMarkSweepGC" 
>> -XX:+CMSParallelRemarkEnabled" 
>> -XX:SurvivorRatio=8" 
>> -XX:MaxTenuringThreshold=1"
>> -XX:CMSInitiatingOccupancyFraction=75"
>> -XX:+UseCMSInitiatingOccupancyOnly"
>> 
>> Memtable Threshold is also:0.75 and rest default cassandra settings
>> 
>> Also we dont have in place a connectionpool for thrift.We are using
cassandra:0.8.6 with solr:3.3
>> 
>> Will share the Cfstats shortly or anything else needed for that
matter.Can you guys help me kn this.
>> 
>> 
>> ==========================================
>> 
>> 
>> Keyspace: system
>>         Read Count: 19
>>         Read Latency: 5.6876842105263155 ms.
>>         Write Count: 2375
>>         Write Latency: 0.010477894736842104 ms.
>>         Pending Tasks: 0
>>                 Column Family: NodeIdInfo
>>                 SSTable count: 0
>>                 Space used (live): 0
>>                 Space used (total): 0
>>                 Number of Keys (estimate): 0
>>                 Memtable Columns Count: 0
>>                 Memtable Data Size: 0
>>                 Memtable Switch Count: 0
>>                 Read Count: 0
>>                 Read Latency: NaN ms.
>>                 Write Count: 0
>>                 Write Latency: NaN ms.
>>                 Pending Tasks: 0
>>                 Key cache capacity: 1
>>                 Key cache size: 0
>>                 Key cache hit rate: NaN
>>                 Row cache: disabled
>>                 Compacted row minimum size: 0
>>                 Compacted row maximum size: 0
>>                 Compacted row mean size: 0
>> 
>>                 Column Family: HintsColumnFamily
>>                 SSTable count: 2
>>                 Space used (live): 492064
>>                 Space used (total): 492064
>>                 Number of Keys (estimate): 256
>>                 Memtable Columns Count: 0
>>                 Memtable Data Size: 0
>>                 Memtable Switch Count: 3
>>                 Read Count: 10
>>                 Read Latency: 5.643 ms.
>>                 Write Count: 2372
>>                 Write Latency: 0.010 ms.
>>                 Pending Tasks: 0
>>                 Key cache capacity: 2
>>                 Key cache size: 2
>>                 Key cache hit rate: 0.42857142857142855
>>                 Row cache: disabled
>>                 Compacted row minimum size: 219343
>>                 Compacted row maximum size: 263210
>>                 Compacted row mean size: 263210
>> 
>>                 Column Family: Schema
>>                 SSTable count: 2
>>                 Space used (live): 20827
>>                 Space used (total): 20827
>>                 Number of Keys (estimate): 256
>>                 Memtable Columns Count: 0
>>                 Memtable Data Size: 0
>>                 Memtable Switch Count: 0
>>                 Read Count: 3
>>                 Read Latency: 4.253 ms.
>>                 Write Count: 0
>>                 Write Latency: NaN ms.
>>                 Pending Tasks: 0
>>                 Key cache capacity: 2
>>                 Key cache size: 2
>>                 Key cache hit rate: 0.0
>>                 Row cache: disabled
>>                 Compacted row minimum size: 104
>>                 Compacted row maximum size: 8239
>>                 Compacted row mean size: 3314
>> 
>>                 Column Family: Migrations
>>                 SSTable count: 2
>>                 Space used (live): 33180
>>                 Space used (total): 33180
>>                 Number of Keys (estimate): 256
>>                 Memtable Columns Count: 0
>>                 Memtable Data Size: 0
>>                 Memtable Switch Count: 0
>>                 Read Count: 0
>>                 Read Latency: NaN ms.
>>                 Write Count: 0
>>                 Write Latency: NaN ms.
>>                 Pending Tasks: 0
>>                 Key cache capacity: 2
>>                 Key cache size: 0
>>                 Key cache hit rate: NaN
>>                 Row cache: disabled
>>                 Compacted row minimum size: 9888
>>                 Compacted row maximum size: 17084
>>                 Compacted row mean size: 14474
>> 
>>                 Column Family: IndexInfo
>>                 SSTable count: 0
>>                 Space used (live): 0
>>                 Space used (total): 0
>>                 Number of Keys (estimate): 0
>>                 Memtable Columns Count: 0
>>                 Memtable Data Size: 0
>>                 Memtable Switch Count: 0
>>                 Read Count: 0
>>                 Read Latency: NaN ms.
>>                 Write Count: 0
>>                 Write Latency: NaN ms.
>>                 Pending Tasks: 0
>>                 Key cache capacity: 1
>>                 Key cache size: 0
>>                 Key cache hit rate: NaN
>>                 Row cache: disabled
>>                 Compacted row minimum size: 0
>>                 Compacted row maximum size: 0
>>                 Compacted row mean size: 0
>> 
>>                 Column Family: LocationInfo
>>                 SSTable count: 3
>>                 Space used (live): 15844
>>                 Space used (total): 15844
>>                 Number of Keys (estimate): 384
>>                 Memtable Columns Count: 0
>>                 Memtable Data Size: 0
>>                 Memtable Switch Count: 2
>>                 Read Count: 6
>>                 Read Latency: 6.479 ms.
>>                 Write Count: 3
>>                 Write Latency: 0.004 ms.
>>                 Pending Tasks: 0
>>                 Key cache capacity: 3
>>                 Key cache size: 3
>>                 Key cache hit rate: 0.3333333333333333
>>                 Row cache: disabled
>>                 Compacted row minimum size: 73
>>                 Compacted row maximum size: 310
>>                 Compacted row mean size: 126
>> 
>> ----------------
>> Keyspace: L
>>         Read Count: 535675
>>         Read Latency: 4.472875136976712 ms.
>>         Write Count: 282216
>>         Write Latency: 0.08156946806701251 ms.
>>         Pending Tasks: 0
>>                 Column Family: FC
>>                 SSTable count: 6
>>                 Space used (live): 444790202
>>                 Space used (total): 444790202
>>                 Number of Keys (estimate): 768
>>                 Memtable Columns Count: 93231
>>                 Memtable Data Size: 172790560
>>                 Memtable Switch Count: 1
>>                 Read Count: 6651
>>                 Read Latency: 62.041 ms.
>>                 Write Count: 94235
>>                 Write Latency: 0.026 ms.
>>                 Pending Tasks: 0
>>                 Key cache: disabled
>>                 Row cache: disabled
>>                 Compacted row minimum size: 104
>>                 Compacted row maximum size: 10090808
>>                 Compacted row mean size: 4256880
>> 
>>                 Column Family: Docs
>>                 SSTable count: 7
>>                 Space used (live): 1487268134
>>                 Space used (total): 1487268134
>>                 Number of Keys (estimate): 303744
>>                 Memtable Columns Count: 98040
>>                 Memtable Data Size: 37732086
>>                 Memtable Switch Count: 1
>>                 Read Count: 125986
>>                 Read Latency: 1.868 ms.
>>                 Write Count: 11900
>>                 Write Latency: 0.520 ms.
>>                 Pending Tasks: 0
>>                 Key cache: disabled
>>                 Row cache: disabled
>>                 Compacted row minimum size: 36
>>                 Compacted row maximum size: 51012
>>                 Compacted row mean size: 5547
>> 
>>                 Column Family: SI
>>                 SSTable count: 3
>>                 Space used (live): 136512555
>>                 Space used (total): 136512555
>>                 Number of Keys (estimate): 286848
>>                 Memtable Columns Count: 5344
>>                 Memtable Data Size: 21139811
>>                 Memtable Switch Count: 1
>>                 Read Count: 27642
>>                 Read Latency: 0.880 ms.
>>                 Write Count: 5815
>>                 Write Latency: 0.093 ms.
>>                 Pending Tasks: 0
>>                 Key cache: disabled
>>                 Row cache: disabled
>>                 Compacted row minimum size: 73
>>                 Compacted row maximum size: 30130992
>>                 Compacted row mean size: 5022190
>> 
>>                 Column Family: TL
>>                 SSTable count: 4
>>                 Space used (live): 314821524
>>                 Space used (total): 314821524
>>                 Number of Keys (estimate): 512
>>                 Memtable Columns Count: 83428
>>                 Memtable Data Size: 16069959
>>                 Memtable Switch Count: 1
>>                 Read Count: 10867
>>                 Read Latency: 17.949 ms.
>>                 Write Count: 5386
>>                 Write Latency: 0.578 ms.
>>                 Pending Tasks: 0
>>                 Key cache: disabled
>>                 Row cache: disabled
>>                 Compacted row minimum size: 12108971
>>                 Compacted row maximum size: 186563160
>>                 Compacted row mean size: 90195666
>> 
>>                 Column Family: TI
>>                 SSTable count: 6
>>                 Space used (live): 1451685937
>>                 Space used (total): 1451685937
>>                 Number of Keys (estimate): 3910144
>>                 Memtable Columns Count: 166006
>>                 Memtable Data Size: 184308808
>>                 Memtable Switch Count: 1
>>                 Read Count: 364529
>>                 Read Latency: 4.194 ms.
>>                 Write Count: 164880
>>                 Write Latency: 0.065 ms.
>>                 Pending Tasks: 0
>>                 Key cache: disabled
>>                 Row cache: disabled
>>                 Compacted row minimum size: 104
>>                 Compacted row maximum size: 7007506
>>                 Compacted row mean size: 18922
>> 
>> ----------------
>> Keyspace: LH
>>         Read Count: 61353
>>         Read Latency: 0.20730264208759147 ms.
>>         Write Count: 56289
>>         Write Latency: 0.13461228659240704 ms.
>>         Pending Tasks: 0
>>                 Column Family: UserPrefrences
>>                 SSTable count: 4
>>                 Space used (live): 335309522
>>                 Space used (total): 335309522
>>                 Number of Keys (estimate): 1513600
>>                 Memtable Columns Count: 12807
>>                 Memtable Data Size: 9144714
>>                 Memtable Switch Count: 1
>>                 Read Count: 20132
>>                 Read Latency: 0.201 ms.
>>                 Write Count: 27817
>>                 Write Latency: 0.009 ms.
>>                 Pending Tasks: 0
>>                 Key cache: disabled
>>                 Row cache: disabled
>>                 Compacted row minimum size: 61
>>                 Compacted row maximum size: 215
>>                 Compacted row mean size: 179
>> 
>>                 Column Family: LastViewedHotels
>>                 SSTable count: 3
>>                 Space used (live): 152316912
>>                 Space used (total): 152316912
>>                 Number of Keys (estimate): 767104
>>                 Memtable Columns Count: 3059
>>                 Memtable Data Size: 2906758
>>                 Memtable Switch Count: 1
>>                 Read Count: 9077
>>                 Read Latency: 0.180 ms.
>>                 Write Count: 3585
>>                 Write Latency: 0.018 ms.
>>                 Pending Tasks: 0
>>                 Key cache: disabled
>>                 Row cache capacity: 10000
>>                 Row cache size: 565
>>                 Row cache hit rate: 0.7896882229811611
>>                 Compacted row minimum size: 36
>>                 Compacted row maximum size: 51012
>>                 Compacted row mean size: 144
>> 
>>                 Column Family: BookedHotels
>>                 SSTable count: 3
>>                 Space used (live): 7274700
>>                 Space used (total): 7274700
>>                 Number of Keys (estimate): 39680
>>                 Memtable Columns Count: 7
>>                 Memtable Data Size: 392
>>                 Memtable Switch Count: 1
>>                 Read Count: 139
>>                 Read Latency: 0.027 ms.
>>                 Write Count: 10
>>                 Write Latency: 0.008 ms.
>>                 Pending Tasks: 0
>>                 Key cache: disabled
>>                 Row cache capacity: 10000
>>                 Row cache size: 4
>>                 Row cache hit rate: 0.2302158273381295
>>                 Compacted row minimum size: 87
>>                 Compacted row maximum size: 35425
>>                 Compacted row mean size: 139
>> 
>>                 Column Family: HotelMessage
>>                 SSTable count: 1
>>                 Space used (live): 349735
>>                 Space used (total): 349735
>>                 Number of Keys (estimate): 512
>>                 Memtable Columns Count: 19424
>>                 Memtable Data Size: 3408866
>>                 Memtable Switch Count: 1
>>                 Read Count: 4726
>>                 Read Latency: 0.059 ms.
>>                 Write Count: 9431
>>                 Write Latency: 0.739 ms.
>>                 Pending Tasks: 0
>>                 Key cache: disabled
>>                 Row cache capacity: 10000
>>                 Row cache size: 144
>>                 Row cache hit rate: 0.968049090139653
>>                 Compacted row minimum size: 87
>>                 Compacted row maximum size: 24601
>>                 Compacted row mean size: 867
>> 
>>                 Column Family: SavedHotels
>>                 SSTable count: 1
>>                 Space used (live): 650153
>>                 Space used (total): 650153
>>                 Number of Keys (estimate): 3456
>>                 Memtable Columns Count: 13
>>                 Memtable Data Size: 728
>>                 Memtable Switch Count: 1
>>                 Read Count: 4282
>>                 Read Latency: 0.029 ms.
>>                 Write Count: 15
>>                 Write Latency: 0.014 ms.
>>                 Pending Tasks: 0
>>                 Key cache: disabled
>>                 Row cache capacity: 10000
>>                 Row cache size: 13
>>                 Row cache hit rate: 0.06819243344231668
>>                 Compacted row minimum size: 104
>>                 Compacted row maximum size: 2299
>>                 Compacted row mean size: 160
>> 
>>                 Column Family: SavedHotelsInverted
>>                 SSTable count: 1
>>                 Space used (live): 646988
>>                 Space used (total): 646988
>>                 Number of Keys (estimate): 3456
>>                 Memtable Columns Count: 13
>>                 Memtable Data Size: 728
>>                 Memtable Switch Count: 1
>>                 Read Count: 13
>>                 Read Latency: 3.014 ms.
>>                 Write Count: 15
>>                 Write Latency: 0.007 ms.
>>                 Pending Tasks: 0
>>                 Key cache: disabled
>>                 Row cache capacity: 10000
>>                 Row cache size: 2
>>                 Row cache hit rate: 0.15384615384615385
>>                 Compacted row minimum size: 104
>>                 Compacted row maximum size: 2299
>>                 Compacted row mean size: 160
>> 
>>                 Column Family: LastViewedHotelsInverted
>>                 SSTable count: 4
>>                 Space used (live): 147678370
>>                 Space used (total): 147678370
>>                 Number of Keys (estimate): 770048
>>                 Memtable Columns Count: 2486
>>                 Memtable Data Size: 2524930
>>                 Memtable Switch Count: 1
>>                 Read Count: 2667
>>                 Read Latency: 0.622 ms.
>>                 Write Count: 3590
>>                 Write Latency: 0.010 ms.
>>                 Pending Tasks: 0
>>                 Key cache: disabled
>>                 Row cache capacity: 10000
>>                 Row cache size: 477
>>                 Row cache hit rate: 0.3820772403449569
>>                 Compacted row minimum size: 36
>>                 Compacted row maximum size: 51012
>>                 Compacted row mean size: 160
>> 
>>                 Column Family: SavedSearchRequest
>>                 SSTable count: 11
>>                 Space used (live): 4560932807
>>                 Space used (total): 4560932807
>>                 Number of Keys (estimate): 1022336
>>                 Memtable Columns Count: 7762
>>                 Memtable Data Size: 17281321
>>                 Memtable Switch Count: 1
>>                 Read Count: 20317
>>                 Read Latency: 0.242 ms.
>>                 Write Count: 11827
>>                 Write Latency: 0.022 ms.
>>                 Pending Tasks: 0
>>                 Key cache: disabled
>>                 Row cache capacity: 10000
>>                 Row cache size: 619
>>                 Row cache hit rate: 0.7583304621745336
>>                 Compacted row minimum size: 925
>>                 Compacted row maximum size: 1955666
>>                 Compacted row mean size: 5014
>> 
>>                 Column Family: HotelTariffs
>>                 SSTable count: 3
>>                 Space used (live): 42775204
>>                 Space used (total): 42775204
>>                 Number of Keys (estimate): 18176
>>                 Memtable Columns Count: 0
>>                 Memtable Data Size: 0
>>                 Memtable Switch Count: 0
>>                 Read Count: 0
>>                 Read Latency: NaN ms.
>>                 Write Count: 0
>>                 Write Latency: NaN ms.
>>                 Pending Tasks: 0
>>                 Key cache: disabled
>>                 Row cache capacity: 10000
>>                 Row cache size: 0
>>                 Row cache hit rate: NaN
>>                 Compacted row minimum size: 180
>>                 Compacted row maximum size: 9887
>>                 Compacted row mean size: 2179
>> 
>> I would appreciate a quick help.
>> 
>> Regards,
>> Shubham
> 
>
 
CD: 4ms