On 2023/09/06 04:22:58 QQ wrote: > Hi Pulsar Community, > > I’d like to start a discussion about whether replacing the customize util > class like ConcurrentOpenHashMap with ConcurrentHashMap, as the performance > of ConcurrentHashMap is better than those customize util significantly. > Worse, these customize util class cannot ensure consistence in method forEach > as PR https://github.com/apache/pulsar/pull/21110 shows, which is > disquieting, although it may not cause any problem. > > Thanks, > The Tumbled. >
The benchmark results is provided in https://github.com/apache/pulsar/pull/20647\#issuecomment-1607257960 <https://github.com/apache/pulsar/pull/20647%5C#issuecomment-1607257960>. > However, iterators are designed to be used by only one thread at a time. Bear > in mind that the results of aggregate status methods including size, isEmpty, > and containsValue are typically useful only when a map is not undergoing > concurrent updates in other threads. Otherwise the results of these methods > reflect transient states that may be adequate for monitoring or estimation > purposes, but not for program control. And I notice that ConcurrentHashMap’s forEach method do not support thread-safety too. It seems that the only reason left for us to replacing the customized util is the superior performance of ConcurrentHashMap. Thanks, The Tumbled.
