Looks like the patch attached earlier is not visible. As this is my
first contribution, please let me know how I can send the patch for review.
On 10/11/17 5:37 PM, Venkateswara R Chintala wrote:
Hi,
In a multi-threaded environment, when java.util.SimpleTimeZone object
is used to create a default timezone, there can be a race condition
between the methods java.util.Timezone.getDefault() and
java.util.Timezone.getDefaultRef() which can result in inconsistency
of cache that is used to validate a particular time/date in DST.
When a thread is cloning a default timezone object (SimpleTimeZone)
and at the same time if a different thread modifies the time/year
values, then the cache values (cacheYear, cacheStart, cacheEnd) can
become inconsistent which leads to incorrect DST determination.
We considered two approaches to fix the issue.
1)Synchronize access to cloning default timezone object when cache is
being modified.
2)Invalidate the cache while returning the clone.
We preferred the second option as synchronization is more expensive.
We have attached the patch and jtreg testcase. Please review.
--
Regards
-Venkat
