update default commitlog segment and total size patch by jbellis; reviewed by vijay for CASSANDRA-4422
Project: http://git-wip-us.apache.org/repos/asf/cassandra/repo Commit: http://git-wip-us.apache.org/repos/asf/cassandra/commit/aa2c28ea Tree: http://git-wip-us.apache.org/repos/asf/cassandra/tree/aa2c28ea Diff: http://git-wip-us.apache.org/repos/asf/cassandra/diff/aa2c28ea Branch: refs/heads/cassandra-1.1 Commit: aa2c28eadea7009361b46d95ee86a46fff291c0b Parents: 9a8a890 Author: Jonathan Ellis <jbel...@apache.org> Authored: Fri Jul 6 13:36:20 2012 -0500 Committer: Jonathan Ellis <jbel...@apache.org> Committed: Fri Jul 6 14:26:58 2012 -0500 ---------------------------------------------------------------------- CHANGES.txt | 2 + conf/cassandra.yaml | 21 ++++++++++----- src/java/org/apache/cassandra/config/Config.java | 4 +- .../cassandra/config/DatabaseDescriptor.java | 6 ++++ 4 files changed, 24 insertions(+), 9 deletions(-) ---------------------------------------------------------------------- http://git-wip-us.apache.org/repos/asf/cassandra/blob/aa2c28ea/CHANGES.txt ---------------------------------------------------------------------- diff --git a/CHANGES.txt b/CHANGES.txt index 4576480..1857671 100644 --- a/CHANGES.txt +++ b/CHANGES.txt @@ -1,4 +1,6 @@ 1.1.3 + * update default commitlog segment size to 32MB and total commitlog + size to 32/1024 MB for 32/64 bit JVMs, respectively (CASSANDRA-4422) * avoid using global partitioner to estimate ranges in index sstables (CASSANDRA-4403) * restore pre-CASSANDRA-3862 approach to removing expired tombstones http://git-wip-us.apache.org/repos/asf/cassandra/blob/aa2c28ea/conf/cassandra.yaml ---------------------------------------------------------------------- diff --git a/conf/cassandra.yaml b/conf/cassandra.yaml index d64e2c9..c4732db 100644 --- a/conf/cassandra.yaml +++ b/conf/cassandra.yaml @@ -155,13 +155,16 @@ saved_caches_directory: /var/lib/cassandra/saved_caches commitlog_sync: periodic commitlog_sync_period_in_ms: 10000 -# Configure the Size of the individual Commitlog file. The -# default is 128 MB, which is almost always fine, but if you are +# The size of the individual commitlog file segments. A commitlog +# segment may be archived, deleted, or recycled once all the data +# in it (potentally from each columnfamily in the system) has been +# flushed to sstables. +# +# The default size is 32, which is almost always fine, but if you are # archiving commitlog segments (see commitlog_archiving.properties), -# then you probably want a finer granularity of archiving; 16 MB +# then you probably want a finer granularity of archiving; 8 or 16 MB # is reasonable. -# -# commitlog_segment_size_in_mb: 128 +commitlog_segment_size_in_mb: 32 # any class that implements the SeedProvider interface and has a # constructor that takes a Map<String, String> of parameters will do. @@ -218,10 +221,14 @@ concurrent_writes: 32 # If omitted, Cassandra will set it to 1/3 of the heap. # memtable_total_space_in_mb: 2048 -# Total space to use for commitlogs. +# Total space to use for commitlogs. Since commitlog segments are +# mmapped, and hence use up address space, the default size is 32 +# on 32-bit JVMs, and 1024 on 64-bit JVMs. +# # If space gets above this value (it will round up to the next nearest # segment multiple), Cassandra will flush every dirty CF in the oldest -# segment and remove it. +# segment and remove it. So a small total commitlog space will tend +# to cause more flush activity on less-active columnfamilies. # commitlog_total_space_in_mb: 4096 # This sets the amount of memtable flush writer threads. These will http://git-wip-us.apache.org/repos/asf/cassandra/blob/aa2c28ea/src/java/org/apache/cassandra/config/Config.java ---------------------------------------------------------------------- diff --git a/src/java/org/apache/cassandra/config/Config.java b/src/java/org/apache/cassandra/config/Config.java index 658c6e6..f749db6 100644 --- a/src/java/org/apache/cassandra/config/Config.java +++ b/src/java/org/apache/cassandra/config/Config.java @@ -97,11 +97,11 @@ public class Config // Commit Log public String commitlog_directory; - public Integer commitlog_total_space_in_mb = 4096; + public Integer commitlog_total_space_in_mb; public CommitLogSync commitlog_sync; public Double commitlog_sync_batch_window_in_ms; public Integer commitlog_sync_period_in_ms; - public int commitlog_segment_size_in_mb = 128; + public int commitlog_segment_size_in_mb = 32; public String endpoint_snitch; public Boolean dynamic_snitch = true; http://git-wip-us.apache.org/repos/asf/cassandra/blob/aa2c28ea/src/java/org/apache/cassandra/config/DatabaseDescriptor.java ---------------------------------------------------------------------- diff --git a/src/java/org/apache/cassandra/config/DatabaseDescriptor.java b/src/java/org/apache/cassandra/config/DatabaseDescriptor.java index 3bafb72..8cb2cba 100644 --- a/src/java/org/apache/cassandra/config/DatabaseDescriptor.java +++ b/src/java/org/apache/cassandra/config/DatabaseDescriptor.java @@ -142,6 +142,9 @@ public class DatabaseDescriptor Yaml yaml = new Yaml(new Loader(constructor)); conf = (Config)yaml.load(input); + if (!System.getProperty("os.arch").contains("64")) + logger.info("32bit JVM detected. It is recommended to run Cassandra on a 64bit JVM for better performance."); + if (conf.commitlog_sync == null) { throw new ConfigurationException("Missing required directive CommitLogSync"); @@ -172,6 +175,9 @@ public class DatabaseDescriptor logger.debug("Syncing log with a period of " + conf.commitlog_sync_period_in_ms); } + if (conf.commitlog_total_space_in_mb == null) + conf.commitlog_total_space_in_mb = System.getProperty("os.arch").contains("64") ? 1024 : 32; + /* evaluate the DiskAccessMode Config directive, which also affects indexAccessMode selection */ if (conf.disk_access_mode == Config.DiskAccessMode.auto) {
