Hi, All, The current webkit database/storage is implemented with creating new threads. But not all platform/products support mulple-threading. Also, threading can be expensive on some platforms. Except this database/storage implementation, WEBKIT platform-crossing code can build and run in a single thread. WEBKIT generally uses WebCore::Timer To avoid blocking UI. Another way to avoid blocking UI is to create a separate thread for UI, and WEBKIT code can still run in a single-thread. Now it's broken by database/storage code, which forces to use multiple threads for WEBKIT. In our WINCE port, we have implemented a single-threaded solution with WebCore::Timer. The patch has been post to https://bugs.webkit.org/show_bug.cgi?id=28019 . The patch is a bit out-of-date, due to changes in upstream. New patch will come soon. Please give some comments if you're interested. There's a macro ENABLE_JSC_MULTIPLE_THREADS used in JSC. Probably there should also be a macro ENABLE_WEBCORE_MULTIPLE_THREADS. Or just use ENABLE_MULTIPLE_THREADS for all multi-threading code. Best regards to everyone, Yong Li