[IGNITE-14898] IndexOutOfBoundException in flusher selection logic in GridCacheWriteBehindStore

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Duplicate
• Affects Version/s: 2.10
• Component/s: general
• Assignee: Ilya Korol
• Reporter: Ilya Korol
• Created: 11/Jun/21 12:05
• Updated: 15/Jun/21 08:39
• Resolved: 15/Jun/21 08:39

Description

There i a bug in GridCacheWriteBehindStore method for selecting which flusher should be used for current data write by specified key:

    /**
     * Return flusher by by key.
     *
     * @param key Key for search.
     * @return flusher.
     */
    private Flusher flusher(K key) {
        int h, idx;

        if (flushThreadCntIsPowerOfTwo)
            idx = ((h = key.hashCode()) ^ (h >>> 16)) & (flushThreadCnt - 1);
        else
            idx = ((h = key.hashCode()) ^ (h >>> 16)) % flushThreadCnt;

        return flushThreads[idx];
    }

In case when flushThreadCount is not a power of 2 and incoming key.hashCode() < 0 (e.g. for UUID string) we will get IndexOutOfBoundException.

http://apache-ignite-users.70518.x6.nabble.com/Bug-in-GridCacheWriteBehindStore-td36189.html

Issue Links

• duplicates: IGNITE-14893 Bug in GridCacheWriteBehindStore Flusher thread lookup