[IBATIS-508] Lock occurs when heavy traffic

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.3.0, 2.3.4
• Fix Version/s: 2.3.5
• Component/s: Core
• Environment: all platform
• Assignee: Kai Grabfelder
• Reporter: Takayuki Ikeda
• Created: 15/May/08 12:48
• Updated: 15/Aug/09 13:43
• Resolved: 01/May/09 11:51

Description

In heavy traffic , lock occurs at com.ibatis.common.beans.ClassInfo#getInstance in case of cacheEnabled = true.
It seems to be happend because of "double synchronized"

ClassInfo.java
—
private static final Map CLASS_INFO_MAP = Collections.synchronizedMap(new HashMap());

public static ClassInfo getInstance(Class clazz) {
if (cacheEnabled) {
synchronized (clazz) {
—
I think we get more concurrency to access getInstance if the synchronized clause in getInstance method is deleted.
There is no side-effect to do this.
#just created several useless ClassInfo objects