From caf6150e9785da408f1e603ae70eae25b5202d98 Mon Sep 17 00:00:00 2001 From: Huang Le <4tarhl@gmail.com> Date: Fri, 27 Jun 2014 02:55:39 +0800 Subject: [PATCH] Use async name resolving to improve net thread responsiveness In the LookupIntern(), things changed are: 1. Call getaddrinfo_a() instead of getaddrinfo() if available, the former is a sync version of the latter; 2. Try using inet_pton()/inet_addr() to convert the input text to a network addr structure at first, if success the extra name resolving thread inside getaddrinfo_a() could be avoided; 3. An interruption point added in the waiting loop for return from getaddrinfo_a(), which completes the improve for thread responsiveness. A easy way to see the effect is to kick off a 'bitcoind stop' immediately after 'bitcoind -daemon', before the change it would take several, or even tens of, minutes on a bad network situation to wait for the running bitcoind to exit, now it costs only seconds. Signed-off-by: Huang Le <4tarhl@gmail.com> --- configure.ac | 2 ++ src/netbase.cpp | 60 ++++++++++++++++++++++++++++++++++++++++++++++++- 2 files changed, 61 insertions(+), 1 deletion(-) diff --git a/configure.ac b/configure.ac index 811ef1dd8..3abf94f13 100644 --- a/configure.ac +++ b/configure.ac @@ -369,6 +369,8 @@ if test x$TARGET_OS = xdarwin; then fi AC_CHECK_HEADERS([endian.h stdio.h stdlib.h unistd.h strings.h sys/types.h sys/stat.h sys/select.h]) +AC_SEARCH_LIBS([getaddrinfo_a], [anl], [AC_DEFINE(HAVE_GETADDRINFO_A, 1, [Define this symbol if you have getaddrinfo_a])]) +AC_SEARCH_LIBS([inet_pton], [nsl resolv], [AC_DEFINE(HAVE_INET_PTON, 1, [Define this symbol if you have inet_pton])]) AC_CHECK_DECLS([le32toh, le64toh, htole32, htole64, be32toh, be64toh, htobe32, htobe64],,, [#if HAVE_ENDIAN_H diff --git a/src/netbase.cpp b/src/netbase.cpp index 3c50174e7..f47b0f356 100644 --- a/src/netbase.cpp +++ b/src/netbase.cpp @@ -3,6 +3,18 @@ // Distributed under the MIT/X11 software license, see the accompanying // file COPYING or http://www.opensource.org/licenses/mit-license.php. +#ifdef HAVE_CONFIG_H +#include "bitcoin-config.h" +#endif + +#ifdef HAVE_INET_PTON +#include +#endif + +#ifdef HAVE_GETADDRINFO_A +#include +#endif + #include "netbase.h" #include "hash.h" @@ -71,9 +83,30 @@ bool static LookupIntern(const char *pszName, std::vector& vIP, unsign } } +#ifdef HAVE_GETADDRINFO_A + struct in_addr ipv4_addr; +#ifdef HAVE_INET_PTON + if (inet_pton(AF_INET, pszName, &ipv4_addr) > 0) { + vIP.push_back(CNetAddr(ipv4_addr)); + return true; + } + + struct in6_addr ipv6_addr; + if (inet_pton(AF_INET6, pszName, &ipv6_addr) > 0) { + vIP.push_back(CNetAddr(ipv6_addr)); + return true; + } +#else + ipv4_addr.s_addr = inet_addr(pszName); + if (ipv4_addr.s_addr != INADDR_NONE) { + vIP.push_back(CNetAddr(ipv4_addr)); + return true; + } +#endif +#endif + struct addrinfo aiHint; memset(&aiHint, 0, sizeof(struct addrinfo)); - aiHint.ai_socktype = SOCK_STREAM; aiHint.ai_protocol = IPPROTO_TCP; aiHint.ai_family = AF_UNSPEC; @@ -82,8 +115,33 @@ bool static LookupIntern(const char *pszName, std::vector& vIP, unsign #else aiHint.ai_flags = fAllowLookup ? AI_ADDRCONFIG : AI_NUMERICHOST; #endif + struct addrinfo *aiRes = NULL; +#ifdef HAVE_GETADDRINFO_A + struct gaicb gcb, *query = &gcb; + memset(query, 0, sizeof(struct gaicb)); + gcb.ar_name = pszName; + gcb.ar_request = &aiHint; + int nErr = getaddrinfo_a(GAI_NOWAIT, &query, 1, NULL); + if (nErr) + return false; + + do { + // Should set the timeout limit to a resonable value to avoid + // generating unnecessary checking call during the polling loop, + // while it can still response to stop request quick enough. + // 2 seconds looks fine in our situation. + struct timespec ts = { 2, 0 }; + gai_suspend(&query, 1, &ts); + boost::this_thread::interruption_point(); + + nErr = gai_error(query); + if (0 == nErr) + aiRes = query->ar_result; + } while (nErr == EAI_INPROGRESS); +#else int nErr = getaddrinfo(pszName, NULL, &aiHint, &aiRes); +#endif if (nErr) return false;