Hi,
What are the possible ways to clear cURL connection cache? One way would be to
close the current multi handle and open a new one. Are there some other
options? I've got a situation where connection cache is kept through internet
connection change (Wifi -> 3G for example). After network change cURL will try
to reuse the connection from cache and will fail and open a new connection. The
problem is that it takes ~20 seconds to understand that the connection was
dead. Are there any ways to overcome this? I'd still like to reuse connections
when possible. I could force requests with CURLOPT_FRESH_CONNECT after network
change for some time but that's not ideal.
Regards,Risto
Here's the example cURL output for this problem:
2016-07-05 15:51:34.155 //First request* STATE: INIT => CONNECT handle
0x8604f8; line 1090 (connection #-5000)* Added connection 0. The cache now
contains 1 members* timeout on name lookup is not supported* Trying
54.175.219.8...* STATE: CONNECT => WAITCONNECT handle 0x8604f8; line 1143
(connection #0)* Connected to www.httpbin.org (54.175.219.8) port 80 (#0)*
STATE: WAITCONNECT => SENDPROTOCONNECT handle 0x8604f8; line 1240 (connection
#0)* STATE: SENDPROTOCONNECT => WAITDO handle 0x8604f8; line 1258 (connection
#0)* STATE: WAITDO => DO handle 0x8604f8; line 1290 (connection #0)* STATE: DO
=> DO_DONE handle 0x8604f8; line 1337 (connection #0)* STATE: DO_DONE =>
WAITPERFORM handle 0x8604f8; line 1464 (connection #0)* STATE: WAITPERFORM =>
PERFORM handle 0x8604f8; line 1474 (connection #0)* STATE: PERFORM => DONE
handle 0x8604f8; line 1632 (connection #0)* Curl_done* Connection #0 to host
www.httpbin.org left intact
2016-07-05 15:52:04.741 //Second request* STATE: INIT => CONNECT handle
0x8604f8; line 1090 (connection #-5000)* Found bundle for host www.httpbin.org:
0x853d38* Re-using existing connection! (#0) with host www.httpbin.org*
Connected to www.httpbin.org (54.175.219.8) port 80 (#0)* STATE: CONNECT =>
WAITDO handle 0x8604f8; line 1136 (connection #0)* STATE: WAITDO => DO handle
0x8604f8; line 1290 (connection #0)* STATE: DO => DO_DONE handle 0x8604f8; line
1337 (connection #0)* STATE: DO_DONE => WAITPERFORM handle 0x8604f8; line 1464
(connection #0)* STATE: WAITPERFORM => PERFORM handle 0x8604f8; line 1474
(connection #0)
2016-07-05 15:52:23.626 //Connection is dead - retry Recv failure: Connection
was reset* Connection died, retrying a fresh connect* Curl_done* Closing
connection 0* The cache now contains 0 members* Issue another request to this
URL: 'http://www.httpbin.org/get'* STATE: PERFORM => CONNECT handle 0x8604f8;
line 1608 (connection #-5000)* Added connection 1. The cache now contains 1
members* timeout on name lookup is not supported* Hostname www.httpbin.org was
found in DNS cache* Trying 54.175.219.8...* STATE: CONNECT => WAITCONNECT
handle 0x8604f8; line 1143 (connection #1)* Connected to www.httpbin.org
(54.175.219.8) port 80 (#1)* STATE: WAITCONNECT => SENDPROTOCONNECT handle
0x8604f8; line 1240 (connection #1)* STATE: SENDPROTOCONNECT => WAITDO handle
0x8604f8; line 1258 (connection #1)* STATE: WAITDO => DO handle 0x8604f8; line
1290 (connection #1)* STATE: DO => DO_DONE handle 0x8604f8; line 1337
(connection #1)* STATE: DO_DONE => WAITPERFORM handle 0x8604f8; line 1464
(connection #1)* STATE: WAITPERFORM => PERFORM handle 0x8604f8; line 1474
(connection #1)* STATE: PERFORM => DONE handle 0x8604f8; line 1632 (connection
#1)* Curl_done* Connection #1 to host www.httpbin.org left intact
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