I am still trying to sort this out. When I run with Oracle's JRE, it does
in fact look like compression is enabled for system tables.
cqlsh> DESCRIBE TABLE system.schema_columnfamilies ;
CREATE TABLE schema_columnfamilies (
keyspace_name text,
columnfamily_name text,
bloom_filter_fp_chance double,
caching text,
column_aliases text,
comment text,
compaction_strategy_class text,
compaction_strategy_options text,
comparator text,
compression_parameters text,
default_read_consistency text,
default_validator text,
default_write_consistency text,
gc_grace_seconds int,
id int,
key_alias text,
key_aliases text,
key_validator text,
local_read_repair_chance double,
max_compaction_threshold int,
min_compaction_threshold int,
populate_io_cache_on_flush boolean,
read_repair_chance double,
replicate_on_write boolean,
subcomparator text,
type text,
value_alias text,
PRIMARY KEY (keyspace_name, columnfamily_name)
) WITH
bloom_filter_fp_chance=0.010000 AND
caching='KEYS_ONLY' AND
comment='ColumnFamily definitions' AND
dclocal_read_repair_chance=0.000000 AND
gc_grace_seconds=8640 AND
read_repair_chance=0.000000 AND
replicate_on_write='true' AND
populate_io_cache_on_flush='false' AND
compaction={'class': 'SizeTieredCompactionStrategy'} AND
compression={'sstable_compression': 'SnappyCompressor'};
Unfortunately the Cassandra instance that was running with IBM Java was on
a test virtual machine that has seen been deleted. Even if system tables
are getting created with compression enabled, I do not see how that would
happen with IBM Java where it fails to load the native snappy library.
CFMetadata.DEFAULT_COMPRESSOR should be null when snappy is not available.
On Fri, May 3, 2013 at 11:00 AM, Edward Capriolo <[email protected]>wrote:
> I did not know the system tables were compressed. That would seem like an
> odd decision you would think that the system tables are small and would not
> benefit from compression much. Is it a static object static object that
> requires initialization even though it is not used?
>
>
> On Fri, May 3, 2013 at 10:19 AM, John Sanda <[email protected]> wrote:
>
>> Is there a way to change the sstable_compression for system tables? I am
>> trying to deploy Cassandra 1.2.2 on a platform with IBM Java and 32 bit
>> arch where the snappy-java native library fails to load. The error I get
>> looks like,
>>
>> ERROR [SSTableBatchOpen:1] 2013-05-02 14:42:42,485 CassandraDaemon.java
>> (line 132) Exception in thread Thread[SSTableBatchOpen:1,5,main]
>> java.lang.RuntimeException: Cannot create CompressionParameters for stored
>> parameters
>> at
>> org.apache.cassandra.io.compress.CompressionMetadata.<init>(CompressionMetadata.java:99)
>> at
>> org.apache.cassandra.io.compress.CompressionMetadata.create(CompressionMetadata.java:63)
>> at
>> org.apache.cassandra.io.util.CompressedSegmentedFile$Builder.complete(CompressedSegmentedFile.java:51)
>> at
>> org.apache.cassandra.io.sstable.SSTableReader.load(SSTableReader.java:404)
>> at
>> org.apache.cassandra.io.sstable.SSTableReader.open(SSTableReader.java:198)
>> at
>> org.apache.cassandra.io.sstable.SSTableReader.open(SSTableReader.java:149)
>> at
>> org.apache.cassandra.io.sstable.SSTableReader$1.run(SSTableReader.java:238)
>> at
>> java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:482)
>> at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:345)
>> at java.util.concurrent.FutureTask.run(FutureTask.java:177)
>> at
>> java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1156)
>> at
>> java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:626)
>> at java.lang.Thread.run(Thread.java:780)
>> Caused by: org.apache.cassandra.exceptions.ConfigurationException:
>> SnappyCompressor.create() threw an error: java.lang.NoClassDefFoundError
>> org.xerial.snappy.Snappy (initialization failure)
>> at
>> org.apache.cassandra.io.compress.CompressionParameters.createCompressor(CompressionParameters.java:179)
>> at
>> org.apache.cassandra.io.compress.CompressionParameters.<init>(CompressionParameters.java:71)
>> at
>> org.apache.cassandra.io.compress.CompressionMetadata.<init>(CompressionMetadata.java:95)
>> ... 12 more
>> Caused by: java.lang.reflect.InvocationTargetException
>> at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
>> at
>> sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:88)
>> at
>> sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:55)
>> at java.lang.reflect.Method.invoke(Method.java:613)
>> at
>> org.apache.cassandra.io.compress.CompressionParameters.createCompressor(CompressionParameters.java:156)
>> ... 14 more
>> Caused by: java.lang.NoClassDefFoundError: org.xerial.snappy.Snappy
>> (initialization failure)
>> at java.lang.J9VMInternals.initialize(J9VMInternals.java:176)
>> at
>> org.apache.cassandra.io.compress.SnappyCompressor.create(SnappyCompressor.java:45)
>> ... 19 more
>> Caused by: org.xerial.snappy.SnappyError: [FAILED_TO_LOAD_NATIVE_LIBRARY]
>> null
>> at org.xerial.snappy.SnappyLoader.load(SnappyLoader.java:229)
>> at org.xerial.snappy.Snappy.<clinit>(Snappy.java:44)
>> at java.lang.J9VMInternals.initializeImpl(Native Method)
>> at java.lang.J9VMInternals.initialize(J9VMInternals.java:236)
>> at
>> org.apache.cassandra.service.CassandraDaemon.setup(CassandraDaemon.java:150)
>> at
>> org.apache.cassandra.service.CassandraDaemon.activate(CassandraDaemon.java:366)
>> at
>> org.apache.cassandra.service.CassandraDaemon.main(CassandraDaemon.java:409)
>>
>>
>> I am not able to change sstable_compression for system tables from either
>> cassandra-cli or from cqlsh. I should point out that the DataStax docs do
>> state that system tables cannot be altered. I was wondering though if there
>> might be another way to do so.
>>
>> Simply not using IBM Java is not an option for me. There is already an
>> issue[1] open with the snappy-java project that I think will address this
>> issue; however, that would involve packaging a new version of snappy-java
>> with Cassandra (when the fix is available). I would like to better
>> understand the impact of switching to a patched and/or upgraded version of
>> snappy-java before making that change.
>>
>> [1] https://github.com/xerial/snappy-java/issues/34
>>
>> Thanks
>>
>> - John
>>
>
>
--
- John
