python3: Added a pooled thread handler.

diff --git a/python3/ashd/serve.py b/python3/ashd/serve.py
index db68a5f..0eddc09 100644 (file)
--- a/python3/ashd/serve.py
+++ b/python3/ashd/serve.py
@@ -1,4 +1,4 @@
-import sys, os, threading, time, logging, select, queue
+import sys, os, threading, time, logging, select, queue, collections
 from . import perf
 
 log = logging.getLogger("ashd.serve")
@@ -194,6 +194,111 @@ class freethread(handler):
                     return
             th.join()
 
+class threadpool(handler):
+    cname = "pool"
+
+    def __init__(self, *, max=25, qsz=100, timeout=None, **kw):
+        super().__init__(**kw)
+        self.current = set()
+        self.clk = threading.Lock()
+        self.ccond = threading.Condition(self.clk)
+        self.queue = collections.deque()
+        self.waiting = set()
+        self.qlk = threading.Lock()
+        self.qcond = threading.Condition(self.qlk)
+        self.max = max
+        self.qsz = qsz
+        self.timeout = timeout
+
+    @classmethod
+    def parseargs(cls, *, max=None, queue=None, abort=None, **args):
+        ret = super().parseargs(**args)
+        if max:
+            ret["max"] = int(max)
+        if queue:
+            ret["qsz"] = int(queue)
+        if abort:
+            ret["timeout"] = int(abort)
+        return ret
+
+    def handle(self, req):
+        start = False
+        with self.qlk:
+            if self.timeout is not None:
+                now = start = time.time()
+                while len(self.queue) >= self.qsz:
+                    self.qcond.wait(start + self.timeout - now)
+                    now = time.time()
+                    if now - start > self.timeout:
+                        os.abort()
+            else:
+                while len(self.current) >= self.qsz:
+                    self.qcond.wait()
+            self.queue.append(req)
+            self.qcond.notify()
+            if len(self.waiting) < 1:
+                start = True
+        if start:
+            with self.clk:
+                if len(self.current) < self.max:
+                    th = reqthread(target=self.run)
+                    th.registered = False
+                    th.start()
+                    while not th.registered:
+                        self.ccond.wait()
+
+    def handle1(self, req):
+        try:
+            env = req.mkenv()
+            with perf.request(env) as reqevent:
+                respiter = req.handlewsgi(env, req.startreq)
+                for data in respiter:
+                    req.write(data)
+                if req.status:
+                    reqevent.response([req.status, req.headers])
+                    req.flushreq()
+                self.ckflush(req)
+        except closed:
+            pass
+        except:
+            log.error("exception occurred when handling request", exc_info=True)
+
+    def run(self):
+        timeout = 10.0
+        th = threading.current_thread()
+        with self.clk:
+            self.current.add(th)
+            th.registered = True
+            self.ccond.notify_all()
+        try:
+            while True:
+                start = now = time.time()
+                with self.qlk:
+                    while len(self.queue) < 1:
+                        self.waiting.add(th)
+                        self.qcond.wait(start + timeout - now)
+                        self.waiting.remove(th)
+                        now = time.time()
+                        if now - start > timeout:
+                            return
+                    req = self.queue.popleft()
+                try:
+                    self.handle1(req)
+                finally:
+                    req.close()
+        finally:
+            with self.clk:
+                self.current.remove(th)
+
+    def close(self):
+        while True:
+            with self.lk:
+                if len(self.current) > 0:
+                    th = next(iter(self.current))
+                else:
+                    return
+            th.join()
+
 class resplex(handler):
     cname = "rplex"