1.0.8 在 2012年4月25日 下午10:38，Philip Shon <philip.s...@gmail.com>写道：
> what version of cassandra are you using. I found a big performance hit > when querying on the secondary index. > > I came across this bug in versions prior to 1.1 > > https://issues.apache.org/jira/browse/CASSANDRA-3545 > > Hope that helps. > > 2012/4/25 Jason Tang <ares.t...@gmail.com> > >> And I found, if I only have the search condition "status", it only scan >> 200 records. >> >> But if I combine another condition "partition" then it scan all records >> because "partition" condition match all records. >> >> But combine with other condition such as "userName", even all "userName" >> is same in the 1,000,000 records, it only scan 200 records. >> >> So it impacted by scan execution plan, if we have several search >> conditions, how it works? Do we have the similar execution plan in >> Cassandra? >> >> >> 在 2012年4月25日 下午9:18，Jason Tang <ares.t...@gmail.com>写道： >> >> Hi >>> >>> We have the such CF, and use secondary index to search for simple >>> data "status", and among 1,000,000 row records, we have 200 records with >>> status we want. >>> >>> But when we start to search, the performance is very poor, and check >>> with the command "./bin/nodetool -h localhost -p 8199 cfstats" , Cassandra >>> read 1,000,000 records, and "Read Latency" is 0.2 ms, so totally it used >>> 200 seconds. >>> >>> It use lots of CPU, and check the stack, all thread in Cassandra is >>> read from socket. >>> >>> So I wonder, how to really use index to find the 200 records instead >>> of scan all rows. (Supper Column?) >>> >>> *ColumnFamily: queue* >>> * Key Validation Class: org.apache.cassandra.db.marshal.BytesType* >>> * Default column value validator: >>> org.apache.cassandra.db.marshal.BytesType* >>> * Columns sorted by: org.apache.cassandra.db.marshal.BytesType* >>> * Row cache size / save period in seconds / keys to save : >>> 0.0/0/all* >>> * Row Cache Provider: >>> org.apache.cassandra.cache.ConcurrentLinkedHashCacheProvider* >>> * Key cache size / save period in seconds: 0.0/0* >>> * GC grace seconds: 0* >>> * Compaction min/max thresholds: 4/32* >>> * Read repair chance: 0.0* >>> * Replicate on write: false* >>> * Bloom Filter FP chance: default* >>> * Built indexes: [queue.idxStatus]* >>> * Column Metadata:* >>> * Column Name: status (737461747573)* >>> * Validation Class: org.apache.cassandra.db.marshal.AsciiType* >>> * Index Name: idxStatus* >>> * Index Type: KEYS* >>> * >>> * >>> BRs >>> //Jason >>> >> >> >
