Hi, I am trying to get my head around to why you need
i >= n || i + n >= nextn https://github.com/openjdk/jdk/blob/af5bf81754072fa5879726cfacb7404892b553f0/src/java.base/share/classes/java/util/concurrent/ConcurrentHashMap.java#L2465 in the transfer method of the CHM. https://github.com/openjdk/jdk/blob/af5bf81754072fa5879726cfacb7404892b553f0/src/java.base/share/classes/java/util/concurrent/ConcurrentHashMap.java#L2426 The reasons why I think that this is not required is because : 1) At a time there can be only 1 active transfer. Since there is only one table variable and only one newTable variable. 2) transferIndex is always set to oldTable.length before a transfer() takes place https://github.com/openjdk/jdk/blob/af5bf81754072fa5879726cfacb7404892b553f0/src/java.base/share/classes/java/util/concurrent/ConcurrentHashMap.java#L2440 3) transferIndex is always set to nextIndex - stride, nextIndex is always set to transferIndex which in turn is always set to n (oldTable.length) https://github.com/openjdk/jdk/blob/af5bf81754072fa5879726cfacb7404892b553f0/src/java.base/share/classes/java/util/concurrent/ConcurrentHashMap.java#L2456 https://github.com/openjdk/jdk/blob/af5bf81754072fa5879726cfacb7404892b553f0/src/java.base/share/classes/java/util/concurrent/ConcurrentHashMap.java#L2452 4) All threads that modifies the CHM must help with the transfer() before finalizing the newTable https://github.com/openjdk/jdk/blob/af5bf81754072fa5879726cfacb7404892b553f0/src/java.base/share/classes/java/util/concurrent/ConcurrentHashMap.java#L2467 Please let me know if I am going wrong anywhere or if there are any code paths which can make i >=n when advance = false Any help would be great. -- Regards, Sreyan Chakravarty
