phpcassa get_range太慢了

Question

我有12行的CF. 每行有6列.我试图$ cf-> get_range('pq_questions','','',1200)它获得所有行但速度太慢(约4-6秒)

Column Family: pq_questions
                SSTable count: 1
                Space used (live): 668363
                Space used (total): 668363
                Number of Keys (estimate): 1280
                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: 1000
                Key cache hit rate: 0.10998439937597504
                Row cache capacity: 1000
                Row cache size: 1000
                Row cache hit rate: 0.0
                Compacted row minimum size: 373
                Compacted row maximum size: 1331
                Compacted row mean size: 574

这很奇怪,但cfstats中的读取延迟是NaN ms 当我调用htopdebian时,我看到最多的负载导致phpcassa 我只有一个节点并使用一致性级别ONE.什么可以导致如此缓慢的查询？

Answer 1

我猜你没有安装C扩展.没有它,类似的查询需要1-2秒.安装它后,相同的查询大约需要0.2秒.

关于NaN读取延迟,不会为get_range_slices(phpcassa中的get_range)捕获延迟.