The mysqlnd query cache is an easy to use client side cache for all PHP MySQL extensions. Learn how it performs compared to the MySQL Server cache when running Oxid eShop and artificial tests on one and two machines.

1. MySQL native driver for PHP: Query cache plugin benchmark impressions

2. mysqlnd_qc: Benchmark impressions Ulf Wendel, Andrey Hristov MySQL Connectors Team Sun Microsystems

6. Conclusions

7. Performance art Performance by number of columns and result set size

9. Apache 2.2.6 (MPM = prefork = default)

10. PHP 5.3.3-dev

11. MySQL 5.1.39-debug Source

12. APC 3.1.3p1

13. Memcache 1.4.3

14. libmemcached 0.37

16. Runs ouf of RAM

18. Box B running MySQL

20. ADOdb Lite, ext/mysql

21. Smarty

22. Demo shop frontpage: ~150 database queries

23. Real-life shop frontpages: >>1k database queries

25. No browsing

26. No ordering

28. We show theoretical maximum, only!

35. Conclusions

36. Oxid, 1 box: PHP/Apache/MySQL CPU bound from 2 clients on, MySQL Server QC wins

37. Oxid, 1 box: 1 vs. 10 clients absolut Higher impact once CPU bound, MySQL Server QC wins

38. Oxid, 1 box: 1 vs. 10 clients relative Relative: 200% – 400%, MySQL Server QC wins

40. No knowledge of transactions

41. No knowledge of temporary tables

42. No knowledge of user variables

43. No knowledge of MERGE and stuff

44. No authentification

46. Oxid, 1 box: theoretical maximum Tuned with cache_no_table = 1, PHP QC w. APC wins

48. PHP tuning irrelevant, if MySQL eats 1 core

50. cache_no_table = 1

51. cache_no_table = 1 = MySQL Server QC

52. Oxid, 1 box: 1 vs. 10 clients tuned Tuned with cache_no_table = 1, PHP QC w. APC wins

54. … and, if you are CPU bound because of MySQL

55. … if your <Oxid> application is I/O bound

56. … and, if your are I/O bound because of MySQL

58. Oxid, 1 box: PHP byte code caching Byte code caching is nothing without query caching

59. Oxid, 1 box: BC gains (1 client) With/without BC compared: 20% - 60% win

60. Oxid, 1 box: QC gains (1 client) Without BC, with/without QC compared: 3% - 75% win

61. Oxid, 1 box: BC + QC gains (1 client) With BC and QC: 3% - 120% win

62. Oxid, 1 box: Use QC and BC together 10 clients: performance improvements up to 180%

64. Turn off fans in summer

65. Oxid, 1 box: CPU bound workload Lower MySQL CPU time in favour of PHP CPU time!

66. Oxid, 1 box: MySQL CPU usage Share cache contents between PHP worker processes

67. Oxid, 1 box: MySQL CPU usage Tuned (cache_no_table=1) to eliminate MySQL usage

68. Oxid, 1 box: goal #1 is fewer queries! Monitor MySQLs' Com_select and Queries statistics

69. Oxid, 2 boxes: PHP/Apache + MySQL PHP QC and MySQL Server QC about equal fast

70. Oxid, 2 boxes: 1 vs. 10 clients Relative: 130 – 200%, CPU bound on PHP/Apache box

71. Oxid, 2 boxes: PHP/Apache + MySQL Tuning (cache_no_table=1), theoretical maximum

73. Why Memcache if using only one PHP machine?

74. Needs to be benchmarked with 3+ boxes

78. Conclusions

79. Performance degration with QC? Rather not - difference is less than 1%

81. Share contents among processes?

82. Share contents among machines?

84. qc_load.php, 1 box: 20s, 100 rows Significant performance differences

85. qc_load.php, 1 box: 20s, 100 rows 1 vs. 10 clients, CPU bound from 2 clients on

86. qc_load.php, 1 box: 20s, 100 rows Handler scalability by number of clients

87. mysqlnd_qc_perf.phpt, Memcache Average speedup: 1.40

88. mysqlnd_qc_perf.phpt, User handler Average speedup: 1.41

89. mysqlnd_qc_perf.phpt, APC Average speedup: 1.48

90. mysqlnd_qc_perf.phpt, Default Average speedup: 1.55

92. MySQL % CPU can be reduced by factor 30!

93. cache as much as you can!

94. cache handler: start with default

96. The End Feedback: ulf.wendel@sun.com The End Feedback: [email_address] , [email_address]