Some more Cassandra tunables.

Makefile

@@ -9,10 +9,12 @@ DISTFILES = thrift-0.9.0.tar.gz;https://dist.apache.org/repos/dist/release/thrif
 FETCH = wget -c --no-check-certificate -O -
 MAKETHREADS = 4
 
-CASSANDRA_FLUSH_LARGEST_MEMTABLES_AT = 0.5
-CASSANDRA_REDUCE_CACHE_SIZES_AT      = 0.6
-CASSANDRA_REDUCE_CACHE_CAPACITY_TO   = 0.4
-CASSANDRA_PARTITIONER                = org.apache.cassandra.dht.ByteOrderedPartitioner
+CASSANDRA_FLUSH_LARGEST_MEMTABLES_AT   = 0.5
+CASSANDRA_REDUCE_CACHE_SIZES_AT        = 0.6
+CASSANDRA_REDUCE_CACHE_CAPACITY_TO     = 0.4
+CASSANDRA_PARTITIONER                  = org.apache.cassandra.dht.ByteOrderedPartitioner
+CASSANDRA_COMMITLOG_TOTAL_SPACE_IN_MB  = 256
+CASSANDRA_COMMITLOG_SEGMENT_SIZE_IN_MB = 16
 
 DISTFILESNAMES = $(foreach f,$(DISTFILES),$(shell echo "$(f)" | sed 's/;.*//'))
 DISTFILESPATHS = $(foreach f,$(DISTFILES),$(shell echo "$(f)" | sed 's/.tar.gz;.*//'))
@@ -93,10 +95,12 @@ $(DCDBDEPSPATH)/.prerequesites: $(DCDBDEPSPATH)/.extract-distfiles
 	@rsync -a $(DCDBDEPSPATH)/$(C)/ $(DCDBDEPLOYPATH)/cassandra
 	@$(eval P := $(shell echo "$(DCDBDEPLOYPATH)" | sed 's/\//\\\//g'))
 	@sed -i.original -e 's/\/var\/lib\/cassandra/$(P)\/var\/lib\/cassandra/g' $(DCDBDEPLOYPATH)/cassandra/conf/cassandra.yaml
-	@sed -i -e 's/flush_largest_memtables_at:.*/flush_largest_memtables_at:\ $(CASSANDRA_FLUSH_LARGEST_MEMTABLES_AT)/' $(DCDBDEPLOYPATH)/cassandra/conf/cassandra.yaml
-	@sed -i -e 's/reduce_cache_sizes_at:.*/reduce_cache_sizes_at:\ $(CASSANDRA_REDUCE_CACHE_SIZES_AT)/' $(DCDBDEPLOYPATH)/cassandra/conf/cassandra.yaml
-	@sed -i -e 's/reduce_cache_capacity_to:.*/reduce_cache_capacity_to:\ $(CASSANDRA_REDUCE_CACHE_CAPACITY_TO)/' $(DCDBDEPLOYPATH)/cassandra/conf/cassandra.yaml
-	@sed -i -e 's/partitioner:.*/partitioner:\ $(CASSANDRA_PARTITIONER)/' $(DCDBDEPLOYPATH)/cassandra/conf/cassandra.yaml
+	@sed -i -e 's/.*flush_largest_memtables_at:.*/flush_largest_memtables_at:\ $(CASSANDRA_FLUSH_LARGEST_MEMTABLES_AT)/' $(DCDBDEPLOYPATH)/cassandra/conf/cassandra.yaml
+	@sed -i -e 's/.*reduce_cache_sizes_at:.*/reduce_cache_sizes_at:\ $(CASSANDRA_REDUCE_CACHE_SIZES_AT)/' $(DCDBDEPLOYPATH)/cassandra/conf/cassandra.yaml
+	@sed -i -e 's/.*reduce_cache_capacity_to:.*/reduce_cache_capacity_to:\ $(CASSANDRA_REDUCE_CACHE_CAPACITY_TO)/' $(DCDBDEPLOYPATH)/cassandra/conf/cassandra.yaml
+	@sed -i -e 's/.*partitioner:.*/partitioner:\ $(CASSANDRA_PARTITIONER)/' $(DCDBDEPLOYPATH)/cassandra/conf/cassandra.yaml
+	@sed -i -e 's/.*commitlog_total_space_in_mb:.*/commitlog_total_space_in_mb: $(CASSANDRA_COMMITLOG_TOTAL_SPACE_IN_MB)/' $(DCDBDEPLOYPATH)/cassandra/conf/cassandra.yaml
+	@sed -i -e 's/.*commitlog_segment_size_in_mb:.*/commitlog_segment_size_in_mb: $(CASSANDRA_COMMITLOG_SEGMENT_SIZE_IN_MB)/' $(DCDBDEPLOYPATH)/cassandra/conf/cassandra.yaml
 	@sed -i.original -e 's/\/var\/log\/cassandra/$(P)\/var\/log\/cassandra/g' $(DCDBDEPLOYPATH)/cassandra/conf/log4j-server.properties
 
 	@touch $(DCDBDEPSPATH)/.prerequesites