You are viewing a plain text version of this content. The canonical link for it is here.
Posted to commits@zookeeper.apache.org by nk...@apache.org on 2020/01/28 14:24:09 UTC
[zookeeper] branch branch-3.6 updated: ZOOKEEPER-1105: wait for
server response in C client zookeeper_close
This is an automated email from the ASF dual-hosted git repository.
nkalmar pushed a commit to branch branch-3.6
in repository https://gitbox.apache.org/repos/asf/zookeeper.git
The following commit(s) were added to refs/heads/branch-3.6 by this push:
new eedf26b ZOOKEEPER-1105: wait for server response in C client zookeeper_close
eedf26b is described below
commit eedf26bb12bc33169ba2756fccd9527c75afe6ca
Author: Mate Szalay-Beko <sz...@gmail.com>
AuthorDate: Tue Jan 28 15:22:30 2020 +0100
ZOOKEEPER-1105: wait for server response in C client zookeeper_close
**Thanks for Lincoln Lee for the original fix!**
In the current implementation, we always get a WARN in server side
("EndOfStreamException: Unable to read additional data from client")
whenever we close a zookeeper handler from the C client. This also happens
in the end of every execution of the command line C client.
The reason is that currently we don't wait for the response from the server
when we initiate the closing of the client connection, and we terminate
the socket on the client side too early.
I tested the patch both on linux and windows. I also tested it both with
NIO and Netty server side socket implementations.
Author: Mate Szalay-Beko <sz...@gmail.com>
Reviewers: Andor Molnar <an...@apache.org>, Norbert Kalmar <nk...@apache.org>
Closes #1176 from symat/ZOOKEEPER-1105
(cherry picked from commit 57be7aedd698cb824ade7373aaa4d8264e1b4eb7)
Signed-off-by: Norbert Kalmar <nk...@apache.org>
---
.../zookeeper-client-c/src/zookeeper.c | 70 ++++++++++++++++++----
1 file changed, 57 insertions(+), 13 deletions(-)
diff --git a/zookeeper-client/zookeeper-client-c/src/zookeeper.c b/zookeeper-client/zookeeper-client-c/src/zookeeper.c
index 7ab5eed..d2b7356 100644
--- a/zookeeper-client/zookeeper-client-c/src/zookeeper.c
+++ b/zookeeper-client/zookeeper-client-c/src/zookeeper.c
@@ -3495,6 +3495,49 @@ static int add_multi_completion(zhandle_t *zh, int xid, void_completion_t dc,
return add_completion(zh, xid, COMPLETION_MULTI, dc, data, 0,0, clist);
}
+/**
+ * After sending the close request, we are waiting for a given millisecs for
+ * getting the answer and/or for the socket to be closed by the server.
+ *
+ * This function should not be called while we still want to process
+ * any response from the server. It must be called after adaptor_finish called,
+ * in order not to mess with the I/O receiver thread in multi-threaded mode.
+ */
+int wait_for_session_to_be_closed(zhandle_t *zh, int timeout_ms)
+{
+ int ret = 0;
+#ifndef WIN32
+ struct pollfd fd_s[1];
+#else
+ fd_set rfds;
+ struct timeval waittime = {timeout_ms / 1000, (timeout_ms % 1000) * 1000};
+#endif
+
+ if (zh == NULL) {
+ return ZBADARGUMENTS;
+ }
+
+#ifndef WIN32
+ fd_s[0].fd = zh->fd->sock;
+ fd_s[0].events = POLLIN;
+ ret = poll(fd_s, 1, timeout_ms);
+#else
+ FD_ZERO(&rfds);
+ FD_SET(zh->fd->sock , &rfds);
+ ret = select(zh->fd->sock + 1, &rfds, NULL, NULL, &waittime);
+#endif
+
+ if (ret == 0){
+ LOG_WARN(LOGCALLBACK(zh), "Timed out (%dms) during waiting for server's reply after sending a close request, sessionId=%#llx\n",
+ timeout_ms, zh->client_id.client_id);
+ } else if (ret < 0) {
+ LOG_WARN(LOGCALLBACK(zh), "System error (%d) happened while waiting for server's reply, sessionId=%#llx\n",
+ ret, zh->client_id.client_id);
+ }
+
+ return ZOK;
+}
+
int zookeeper_close(zhandle_t *zh)
{
int rc=ZOK;
@@ -3520,32 +3563,33 @@ int zookeeper_close(zhandle_t *zh)
}
/* No need to decrement the counter since we're just going to
* destroy the handle later. */
- if (is_connected(zh)){
+ if (is_connected(zh)) {
struct oarchive *oa;
struct RequestHeader h = {get_xid(), ZOO_CLOSE_OP};
LOG_INFO(LOGCALLBACK(zh), "Closing zookeeper sessionId=%#llx to %s\n",
- zh->client_id.client_id,zoo_get_current_server(zh));
+ zh->client_id.client_id, zoo_get_current_server(zh));
oa = create_buffer_oarchive();
rc = serialize_RequestHeader(oa, "header", &h);
- rc = rc < 0 ? rc : queue_buffer_bytes(&zh->to_send, get_buffer(oa),
- get_buffer_len(oa));
+ rc = rc < 0 ? rc : queue_buffer_bytes(&zh->to_send, get_buffer(oa), get_buffer_len(oa));
/* We queued the buffer, so don't free it */
close_buffer_oarchive(&oa, 0);
if (rc < 0) {
+ LOG_DEBUG(LOGCALLBACK(zh), "Error during closing zookeeper session, sessionId=%#llx to %s (error: %d)\n",
+ zh->client_id.client_id, zoo_get_current_server(zh), rc);
rc = ZMARSHALLINGERROR;
- goto finish;
- }
+ } else {
+ /* make sure the close request is sent; we set timeout to an arbitrary
+ * (but reasonable) number of milliseconds since we want the call to block*/
+ rc = adaptor_send_queue(zh, 3000);
- /* make sure the close request is sent; we set timeout to an arbitrary
- * (but reasonable) number of milliseconds since we want the call to block*/
- rc=adaptor_send_queue(zh, 3000);
- }else{
- LOG_INFO(LOGCALLBACK(zh), "Freeing zookeeper resources for sessionId=%#llx\n",
- zh->client_id.client_id);
+ /* give some time to the server to process the session close request properly */
+ rc = rc < 0 ? rc : wait_for_session_to_be_closed(zh, 1500);
+ }
+ } else {
rc = ZOK;
}
-finish:
+ LOG_INFO(LOGCALLBACK(zh), "Freeing zookeeper resources for sessionId=%#llx\n", zh->client_id.client_id);
destroy(zh);
adaptor_destroy(zh);
free(zh->fd);