[#CONC-196] alloc_root is about 4 times slower (compared to libmysql)

[CONC-196] alloc_root is about 4 times slower (compared to libmysql) Created: 2016-08-03 Updated: 2017-04-03 Resolved: 2016-08-03
Status:	Closed
Project:	MariaDB Connector/C
Component/s:	None
Affects Version/s:	3.0.0, 2.3.0
Fix Version/s:	3.0.1, 2.3.1

Type:

Bug

Priority:

Major

Reporter:

Georg Richter

Assignee:

Georg Richter

Resolution:

Fixed

Votes:

Labels:

None

Issue Links:

Problem/Incident
causes	~~ODBC-31~~	High CPU usage and low network utiliz...	Closed

Description

Due to unnecessary loops alloc_root() function is about 4 times slower.
For a complete description and test case please check ~~ODBC-31~~

Comments

Comment by Georg Richter [ 2016-08-03 ]

Fixed in revisions:
C/C 3.0.1: 7b146034383085bff38b19d9f6399a90896faf02
C/C 2.3.1: ac6078066c26473009fbea2f29cabed87a4f4466

Comment by René Cannaò [ 2017-04-03 ]

Georg, in ac6078066c26473009fbea2f29cabed87a4f4466 , the multiplier here was chosen randomly?
For ProxySQL (that uses libmariadbclient) and sysbench workload, replacing

(mem_root->block_size & ~1) * (mem_root->block_num >> 2)

with

(mem_root->block_size & ~1) * 2

improves performance by 10x

Generated at Thu Feb 08 03:03:34 UTC 2024 using Jira 8.20.16#820016-sha1:9d11dbea5f4be3d4cc21f03a88dd11d8c8687422.