我正在对 TokuDB 引擎进行一些性能测试（我在 Dell PowerEdge R720 上使用了来自 Tokutek 网站的 mariadb-5.5.30-tokudb-7.0.4，内存为 128GB，TokuDB 的默认内存分配为 64GB - tokudb_cache_size）和真正出乎意料的事情发生了。
在测试场景中，我在一个空表（33 列，1 个主 auto_increment 键，5 个索引）上插入了大约90M 行，虽然我注意到与 MyISAM 引擎相比显着的速度性能和数据压缩，即从15K 到 20K 记录/秒并且使用 TokuDB将 30G 数据变为 7G，查询性能急剧下降（没有索引聚集）。
特别是简单的查询：select count(*) from test_table；MyISAM 耗时 0.0001 秒，而TokuDB 耗时20 秒。还有扫描所有 90M 行表的查询（其中 column_not_indexed = something），MyISAM 大约需要2 分钟，而TokuDB的持续时间超过5 分钟！所有其他查询也有性能下降。它们中没有一个比具有相同大小表的 MyISAM 更好。
因此，虽然我了解到 TokuDB 使用的分形树索引在查询速度方面具有出色的性能，但这并没有发生。测试过 TokuDB 的人是否有同样的问题，或者可以提供有关如何提高查询性能的提示？
创建表语句为：
CREATE TABLE `table` (
`Event` bigint(20) NOT NULL AUTO_INCREMENT,
`TimeStamp` bigint(20) NOT NULL DEFAULT '0',
`Field_1` smallint(4) NOT NULL DEFAULT '0',
`Field_2` bigint(12) NOT NULL DEFAULT '0',
`Field_3` varchar(40) NOT NULL DEFAULT '',
`Field_4` bigint(15) DEFAULT NULL,
(...)
PRIMARY KEY (`Event`) USING BTREE,
KEY `Index_ts` (`Timestamp`),
KEY `Index_1` (`Field_1`),
KEY `Index_2` (`Field_2`),
KEY `Index_3` (`Field_3`)
)ENGINE=TokuDB DEFAULT CHARSET=latin1
一些查询是：
SELECT count(*) FROM table
**MyISAM:0.00981429 TokuDB:21.40218998**
SELECT Field_2, Timestamp FROM table IGNORE KEY (Index_3, Index_1) WHERE (Field_3 LIKE "%asweb.be") AND (Field_1 < 42) ORDER BY Timestamp LIMIT 2000
**MyISAM:125.9707183 TokuDB:356.6146628**
SELECT Field_2, Timestamp FROM table IGNORE KEY (Index_1) WHERE (Field_4 = "206012216849912") AND (Field_1 < 42) ORDER BY Timestamp LIMIT 2000
**MyISAM:120.0966643 TokuDB:293.2259202**
SELECT Field_2, Timestamp FROM table IGNORE KEY (Index_1) WHERE (Field_2 = "32475731333") AND (Field_1 < 42) ORDER BY Timestamp LIMIT 100000
**MyISAM:0.00552937 TokuDB:0.18659729**
还：
Query 1: SHOW PROFILE CPU FOR QUERY 1;
Status Duration CPU_user CPU_system
Queried about 88450000 rows 0.001905 0 0
Queried about 88460000 rows 0.001902 0.004 0
Queried about 88470000 rows 0.001906 0 0
Queried about 88480000 rows 0.001905 0.004 0
Queried about 88490000 rows 0.001664 0 0
Queried about 88500000 rows 0.001907 0.004 0
Queried about 88510000 rows 0.001898 0 0
Queried about 88520000 rows 0.001903 0.004001 0
Queried about 88530000 rows 0.001902 0 0
Queried about 88540000 rows 0.001903 0.004 0
Queried about 88550000 rows 0.001661 0 0
Queried about 88560000 rows 0.001905 0 0
Queried about 88570000 rows 0.001901 0.004 0
Queried about 88580000 rows 0.001912 0 0
Queried about 88590000 rows 0.001902 0.004 0
Queried about 88600000 rows 0.001908 0 0
Queried about 88610000 rows 0.001664 0.004001 0
Queried about 88620000 rows 0.001899 0 0
Queried about 88630000 rows 0.001905 0.004 0
Queried about 88640000 rows 0.001901 0 0
Queried about 88650000 rows 0.0019 0.004 0
Queried about 88660000 rows 0.001661 0 0
Queried about 88670000 rows 0.001906 0.004 0
Queried about 88680000 rows 0.001895 0 0
Queried about 88690000 rows 0.001907 0 0
Queried about 88700000 rows 0.001907 0.004001 0
Queried about 88710000 rows 0.001905 0 0
Queried about 88720000 rows 0.001663 0.004 0
Queried about 88730000 rows 0.001905 0 0
Queried about 88740000 rows 0.001903 0.004 0
Queried about 88750000 rows 0.001899 0 0
Queried about 88760000 rows 0.001898 0.004 0
Queried about 88770000 rows 0.001898 0 0
Queried about 88780000 rows 0.001665 0.004001 0
Queried about 88790000 rows 0.0019 0 0
Queried about 88800000 rows 0.001903 0.004 0
Queried about 88810000 rows 0.001909 0 0
Queried about 88820000 rows 0.001903 0.004 0
Queried about 88830000 rows 0.001663 0 0
Queried about 88840000 rows 0.001902 0 0
Queried about 88850000 rows 0.001901 0.004 0
Queried about 88860000 rows 0.001903 0 0
Queried about 88870000 rows 0.0019 0.004001 0
Queried about 88880000 rows 0.001904 0 0
Queried about 88890000 rows 0.001662 0.004 0
Queried about 88900000 rows 0.001903 0 0
Queried about 88910000 rows 0.001901 0.004 0
Queried about 88920000 rows 0.001905 0 0
Queried about 88930000 rows 0.001904 0.004 0
Queried about 88940000 rows 0.001898 0 0
Queried about 88950000 rows 0.001666 0.004001 0
Queried about 88960000 rows 0.001901 0 0
Queried about 88970000 rows 0.001905 0.004 0
Queried about 88980000 rows 0.001899 0 0
Queried about 88990000 rows 0.001907 0 0
Queried about 89000000 rows 0.00166 0.004 0
Queried about 89010000 rows 0.001903 0 0
Queried about 89020000 rows 0.001899 0.004 0
Queried about 89030000 rows 0.001905 0 0
Queried about 89040000 rows 0.0019 0.004001 0
Queried about 89050000 rows 0.0019 0 0
Queried about 89060000 rows 0.001662 0.004 0
Queried about 89070000 rows 0.001897 0 0
Queried about 89080000 rows 0.001901 0.004 0
Queried about 89090000 rows 0.001894 0 0
Queried about 89100000 rows 0.001897 0.004 0
Queried about 89110000 rows 0.001891 0 0
Queried about 89120000 rows 0.001667 0 0
Queried about 89130000 rows 0.001899 0.004001 0
Queried about 89140000 rows 0.001901 0 0
Queried about 89150000 rows 0.001903 0.004 0
Queried about 89160000 rows 0.00191 0 0
Queried about 89170000 rows 0.001662 0.004 0
Queried about 89180000 rows 0.001906 0 0
Queried about 89190000 rows 0.001903 0.004 0
Queried about 89200000 rows 0.0019 0 0
Queried about 89210000 rows 0.001904 0.004001 0
Queried about 89220000 rows 0.001897 0 0
Queried about 89230000 rows 0.001663 0.004 0
Queried about 89240000 rows 0.001902 0 0
Queried about 89250000 rows 0.001906 0 0
Queried about 89260000 rows 0.001905 0.004 0
Queried about 89270000 rows 0.001903 0 0
Queried about 89280000 rows 0.001894 0.004 0
Queried about 89290000 rows 0.00166 0 0
Queried about 89300000 rows 0.001903 0.004001 0
Queried about 89310000 rows 0.001901 0 0
Queried about 89320000 rows 0.0019 0.004 0
Queried about 89330000 rows 0.001904 0 0
Queried about 89340000 rows 0.001661 0.004 0
Queried about 89350000 rows 0.001892 0 0
Queried about 89360000 rows 0.001808 0.004 0
Queried about 89370000 rows 0.000027 0 0
end 0.000008 0 0
query end 0.000008 0 0
closing tables 0.000008 0 0
freeing items 0.000007 0 0
updating status 0.000029 0 0
logging slow query 0.000005 0 0
cleaning up 0.000005 0 0
闻起来像虫子？