1 # This file is part of NIT (http://www.nitlanguage.org).
3 # Licensed under the Apache License, Version 2.0 (the "License");
4 # you may not use this file except in compliance with the License.
5 # You may obtain a copy of the License at
7 # http://www.apache.org/licenses/LICENSE-2.0
9 # Unless required by applicable law or agreed to in writing, software
10 # distributed under the License is distributed on an "AS IS" BASIS,
11 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 # See the License for the specific language governing permissions and
13 # limitations under the License.
15 # Introduces a minimal ThreadPool implementation using Tasks
18 intrude import pthreads
19 import concurrent_collections
21 # A simple ThreadPool implemented with an array
23 private var queue
= new ConcurrentList[Task].wrap
(new List[Task])
24 private var mutex
= new Mutex
25 private var cond
= new NativePthreadCond
27 # Number of threads used
28 var nb_threads
: Int is noinit
31 for i
in [0..nb_threads
[ do
32 var t
= new PoolThread(queue
, mutex
, cond
)
37 private fun set_nb_threads
(nb
: nullable Int) is autoinit
do nb_threads
= nb
or else 5
39 # Adds a Task into the queue
40 fun execute
(task
: Task) do
46 # A Thread running in a threadpool
47 private class PoolThread
50 var queue
: ConcurrentList[Task]
52 var cond
: NativePthreadCond
56 var t
: nullable Task = null
58 if queue
.is_empty
then cond
.wait
(mutex
.native
.as(not null))
59 if not queue
.is_empty
then
63 if t
!= null then t
.main