On Jul 21, 2011, at 6:08 AM, Steinmaurer Thomas wrote: > The client can be configured on how many concurrent clients (one thread > per client), number of records per client etc ... The thing is, even > with only one client (thread), the java process consumes a lot more > threads, which is getting beyond 1000 threads when simulating a load > with 100 clients with this test application.
Are you using HTablePool? If not, you may get excess threads if you create many HTable instances and don't call close on them. That was the cause of my thread explosion. Each HTable instance has a ThreadPoolExecutor with a 60-second timeout, so if you don't call close after your work is done, an extra thread will be left idle until the timeout expires. (And if you're not on 0.90.3 with HBASE-3712 fixed, even calling close won't help.) Using HTablePool solves the problem by limiting the number of HTable instances that are created and recycling them. joe
