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Posted to user@cassandra.apache.org by Ran Tavory <ra...@gmail.com> on 2010/05/24 07:34:27 UTC
Key cache capacity: 1 when using KeysCached="50%"
I've noticed that when defining KeysCached="50%" (or KeysCached="100%" and I
didn't test other values with %) then cfstats reports Key cache capacity: 1
This looks weird... is this expected? (version 0.6.1)
For example, in the default configuration:
<ColumnFamily Name="Super2"
ColumnType="Super"
CompareWith="UTF8Type"
CompareSubcolumnsWith="UTF8Type"
RowsCached="10000"
KeysCached="50%"/>
----------------
Keyspace: Keyspace1
Read Count: 0
Read Latency: NaN ms.
Write Count: 0
Write Latency: NaN ms.
Pending Tasks: 0
Column Family: Super1
SSTable count: 0
Space used (live): 0
Space used (total): 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: 200000
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: Super2
SSTable count: 0
Space used (live): 0
Space used (total): 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 capacity: 10000
Row cache size: 0
Row cache hit rate: NaN
Compacted row minimum size: 0
Compacted row maximum size: 0
Compacted row mean size: 0
Re: Key cache capacity: 1 when using KeysCached="50%"
Posted by Ran Tavory <ra...@gmail.com>.
https://issues.apache.org/jira/browse/CASSANDRA-1129
On Tue, May 25, 2010 at 3:42 PM, Jonathan Ellis <jb...@gmail.com> wrote:
> That does look like a bug. Can you create a ticket and upload a
> (preferably small-ish) sstable that illustrates the problem?
>
> On Mon, May 24, 2010 at 12:07 PM, Ran Tavory <ra...@gmail.com> wrote:
> > I'd like to have 100% keys cached. Sorry if my example of Super2 wasn't
> > correct, but I do think there's a problem. Here's with my own data:
> > When using actual numbers (in this case for RowsCached) it works as
> > expected, however when specifying KeysCached="100%" I get only 1.
> > <ColumnFamily CompareWith="BytesType" Name="KvAds"
> > KeysCached="100%"
> > RowsCached="10000"
> > />
> >
> > Column Family: KvAds
> > SSTable count: 7
> > Space used (live): 797535964
> > Space used (total): 797535964
> > Memtable Columns Count: 42292
> > Memtable Data Size: 10514176
> > Memtable Switch Count: 24
> > Read Count: 2563704
> > Read Latency: 4.590 ms.
> > Write Count: 1963804
> > Write Latency: 0.025 ms.
> > Pending Tasks: 0
> > Key cache capacity: 1
> > Key cache size: 1
> > Key cache hit rate: 0.0
> > Row cache capacity: 10000
> > Row cache size: 10000
> > Row cache hit rate: 0.2206178354382234
> > Compacted row minimum size: 386
> > Compacted row maximum size: 9808
> > Compacted row mean size: 616
> >
> > On Mon, May 24, 2010 at 6:30 PM, Jonathan Ellis <jb...@gmail.com>
> wrote:
> >>
> >> If you really want a cache capacity of 0 then you need to use 0
> >> explicitly, otherwise the % versions will give you at least 1.
> >>
> >> On Mon, May 24, 2010 at 12:34 AM, Ran Tavory <ra...@gmail.com> wrote:
> >> > I've noticed that when defining KeysCached="50%" (or KeysCached="100%"
> >> > and I
> >> > didn't test other values with %) then cfstats reports Key cache
> >> > capacity: 1
> >> > This looks weird... is this expected? (version 0.6.1)
> >> > For example, in the default configuration:
> >> > <ColumnFamily Name="Super2"
> >> > ColumnType="Super"
> >> > CompareWith="UTF8Type"
> >> > CompareSubcolumnsWith="UTF8Type"
> >> > RowsCached="10000"
> >> > KeysCached="50%"/>
> >> >
> >> > ----------------
> >> > Keyspace: Keyspace1
> >> > Read Count: 0
> >> > Read Latency: NaN ms.
> >> > Write Count: 0
> >> > Write Latency: NaN ms.
> >> > Pending Tasks: 0
> >> > Column Family: Super1
> >> > SSTable count: 0
> >> > Space used (live): 0
> >> > Space used (total): 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: 200000
> >> > 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: Super2
> >> > SSTable count: 0
> >> > Space used (live): 0
> >> > Space used (total): 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 capacity: 10000
> >> > Row cache size: 0
> >> > Row cache hit rate: NaN
> >> > Compacted row minimum size: 0
> >> > Compacted row maximum size: 0
> >> > Compacted row mean size: 0
> >> >
> >>
> >>
> >>
> >> --
> >> Jonathan Ellis
> >> Project Chair, Apache Cassandra
> >> co-founder of Riptano, the source for professional Cassandra support
> >> http://riptano.com
> >
> >
>
>
>
> --
> Jonathan Ellis
> Project Chair, Apache Cassandra
> co-founder of Riptano, the source for professional Cassandra support
> http://riptano.com
>
Re: Key cache capacity: 1 when using KeysCached="50%"
Posted by Jonathan Ellis <jb...@gmail.com>.
That does look like a bug. Can you create a ticket and upload a
(preferably small-ish) sstable that illustrates the problem?
On Mon, May 24, 2010 at 12:07 PM, Ran Tavory <ra...@gmail.com> wrote:
> I'd like to have 100% keys cached. Sorry if my example of Super2 wasn't
> correct, but I do think there's a problem. Here's with my own data:
> When using actual numbers (in this case for RowsCached) it works as
> expected, however when specifying KeysCached="100%" I get only 1.
> <ColumnFamily CompareWith="BytesType" Name="KvAds"
> KeysCached="100%"
> RowsCached="10000"
> />
>
> Column Family: KvAds
> SSTable count: 7
> Space used (live): 797535964
> Space used (total): 797535964
> Memtable Columns Count: 42292
> Memtable Data Size: 10514176
> Memtable Switch Count: 24
> Read Count: 2563704
> Read Latency: 4.590 ms.
> Write Count: 1963804
> Write Latency: 0.025 ms.
> Pending Tasks: 0
> Key cache capacity: 1
> Key cache size: 1
> Key cache hit rate: 0.0
> Row cache capacity: 10000
> Row cache size: 10000
> Row cache hit rate: 0.2206178354382234
> Compacted row minimum size: 386
> Compacted row maximum size: 9808
> Compacted row mean size: 616
>
> On Mon, May 24, 2010 at 6:30 PM, Jonathan Ellis <jb...@gmail.com> wrote:
>>
>> If you really want a cache capacity of 0 then you need to use 0
>> explicitly, otherwise the % versions will give you at least 1.
>>
>> On Mon, May 24, 2010 at 12:34 AM, Ran Tavory <ra...@gmail.com> wrote:
>> > I've noticed that when defining KeysCached="50%" (or KeysCached="100%"
>> > and I
>> > didn't test other values with %) then cfstats reports Key cache
>> > capacity: 1
>> > This looks weird... is this expected? (version 0.6.1)
>> > For example, in the default configuration:
>> > <ColumnFamily Name="Super2"
>> > ColumnType="Super"
>> > CompareWith="UTF8Type"
>> > CompareSubcolumnsWith="UTF8Type"
>> > RowsCached="10000"
>> > KeysCached="50%"/>
>> >
>> > ----------------
>> > Keyspace: Keyspace1
>> > Read Count: 0
>> > Read Latency: NaN ms.
>> > Write Count: 0
>> > Write Latency: NaN ms.
>> > Pending Tasks: 0
>> > Column Family: Super1
>> > SSTable count: 0
>> > Space used (live): 0
>> > Space used (total): 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: 200000
>> > 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: Super2
>> > SSTable count: 0
>> > Space used (live): 0
>> > Space used (total): 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 capacity: 10000
>> > Row cache size: 0
>> > Row cache hit rate: NaN
>> > Compacted row minimum size: 0
>> > Compacted row maximum size: 0
>> > Compacted row mean size: 0
>> >
>>
>>
>>
>> --
>> Jonathan Ellis
>> Project Chair, Apache Cassandra
>> co-founder of Riptano, the source for professional Cassandra support
>> http://riptano.com
>
>
--
Jonathan Ellis
Project Chair, Apache Cassandra
co-founder of Riptano, the source for professional Cassandra support
http://riptano.com
Re: Key cache capacity: 1 when using KeysCached="50%"
Posted by Ran Tavory <ra...@gmail.com>.
I'd like to have 100% keys cached. Sorry if my example of Super2 wasn't
correct, but I do think there's a problem. Here's with my own data:
When using actual numbers (in this case for RowsCached) it works as
expected, however when specifying KeysCached="100%" I get only 1.
<ColumnFamily CompareWith="BytesType" Name="KvAds"
KeysCached="100%"
RowsCached="10000"
/>
Column Family: KvAds
SSTable count: 7
Space used (live): 797535964
Space used (total): 797535964
Memtable Columns Count: 42292
Memtable Data Size: 10514176
Memtable Switch Count: 24
Read Count: 2563704
Read Latency: 4.590 ms.
Write Count: 1963804
Write Latency: 0.025 ms.
Pending Tasks: 0
Key cache capacity: 1
Key cache size: 1
Key cache hit rate: 0.0
Row cache capacity: 10000
Row cache size: 10000
Row cache hit rate: 0.2206178354382234
Compacted row minimum size: 386
Compacted row maximum size: 9808
Compacted row mean size: 616
On Mon, May 24, 2010 at 6:30 PM, Jonathan Ellis <jb...@gmail.com> wrote:
> If you really want a cache capacity of 0 then you need to use 0
> explicitly, otherwise the % versions will give you at least 1.
>
> On Mon, May 24, 2010 at 12:34 AM, Ran Tavory <ra...@gmail.com> wrote:
> > I've noticed that when defining KeysCached="50%" (or KeysCached="100%"
> and I
> > didn't test other values with %) then cfstats reports Key cache capacity:
> 1
> > This looks weird... is this expected? (version 0.6.1)
> > For example, in the default configuration:
> > <ColumnFamily Name="Super2"
> > ColumnType="Super"
> > CompareWith="UTF8Type"
> > CompareSubcolumnsWith="UTF8Type"
> > RowsCached="10000"
> > KeysCached="50%"/>
> >
> > ----------------
> > Keyspace: Keyspace1
> > Read Count: 0
> > Read Latency: NaN ms.
> > Write Count: 0
> > Write Latency: NaN ms.
> > Pending Tasks: 0
> > Column Family: Super1
> > SSTable count: 0
> > Space used (live): 0
> > Space used (total): 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: 200000
> > 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: Super2
> > SSTable count: 0
> > Space used (live): 0
> > Space used (total): 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 capacity: 10000
> > Row cache size: 0
> > Row cache hit rate: NaN
> > Compacted row minimum size: 0
> > Compacted row maximum size: 0
> > Compacted row mean size: 0
> >
>
>
>
> --
> Jonathan Ellis
> Project Chair, Apache Cassandra
> co-founder of Riptano, the source for professional Cassandra support
> http://riptano.com
>
Re: Key cache capacity: 1 when using KeysCached="50%"
Posted by Jonathan Ellis <jb...@gmail.com>.
If you really want a cache capacity of 0 then you need to use 0
explicitly, otherwise the % versions will give you at least 1.
On Mon, May 24, 2010 at 12:34 AM, Ran Tavory <ra...@gmail.com> wrote:
> I've noticed that when defining KeysCached="50%" (or KeysCached="100%" and I
> didn't test other values with %) then cfstats reports Key cache capacity: 1
> This looks weird... is this expected? (version 0.6.1)
> For example, in the default configuration:
> <ColumnFamily Name="Super2"
> ColumnType="Super"
> CompareWith="UTF8Type"
> CompareSubcolumnsWith="UTF8Type"
> RowsCached="10000"
> KeysCached="50%"/>
>
> ----------------
> Keyspace: Keyspace1
> Read Count: 0
> Read Latency: NaN ms.
> Write Count: 0
> Write Latency: NaN ms.
> Pending Tasks: 0
> Column Family: Super1
> SSTable count: 0
> Space used (live): 0
> Space used (total): 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: 200000
> 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: Super2
> SSTable count: 0
> Space used (live): 0
> Space used (total): 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 capacity: 10000
> Row cache size: 0
> Row cache hit rate: NaN
> Compacted row minimum size: 0
> Compacted row maximum size: 0
> Compacted row mean size: 0
>
--
Jonathan Ellis
Project Chair, Apache Cassandra
co-founder of Riptano, the source for professional Cassandra support
http://riptano.com
RE: Key cache capacity: 1 when using KeysCached="50%"
Posted by Stu Hood <st...@rackspace.com>.
50% of 0 will be rounded up to 1.
-----Original Message-----
From: "Ran Tavory" <ra...@gmail.com>
Sent: Monday, May 24, 2010 12:34am
To: user@cassandra.apache.org
Subject: Key cache capacity: 1 when using KeysCached="50%"
I've noticed that when defining KeysCached="50%" (or KeysCached="100%" and I
didn't test other values with %) then cfstats reports Key cache capacity: 1
This looks weird... is this expected? (version 0.6.1)
For example, in the default configuration:
<ColumnFamily Name="Super2"
ColumnType="Super"
CompareWith="UTF8Type"
CompareSubcolumnsWith="UTF8Type"
RowsCached="10000"
KeysCached="50%"/>
----------------
Keyspace: Keyspace1
Read Count: 0
Read Latency: NaN ms.
Write Count: 0
Write Latency: NaN ms.
Pending Tasks: 0
Column Family: Super1
SSTable count: 0
Space used (live): 0
Space used (total): 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: 200000
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: Super2
SSTable count: 0
Space used (live): 0
Space used (total): 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 capacity: 10000
Row cache size: 0
Row cache hit rate: NaN
Compacted row minimum size: 0
Compacted row maximum size: 0
Compacted row mean size: 0