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| author | Igor Slepchin <[email protected]> | 2018-09-24 22:44:03 -0400 |
|---|---|---|
| committer | Igor Slepchin <[email protected]> | 2018-10-11 01:07:19 -0400 |
| commit | 210665e8a252faecf28ccebade999e734ab92582 (patch) | |
| tree | 8b81350cb43fd9a59ea13e34e03017f82fccbef3 /erts/emulator | |
| parent | 3daef1a4ee8cfce90d0220be3695809ccbb8ea58 (diff) | |
| download | otp-210665e8a252faecf28ccebade999e734ab92582.tar.gz otp-210665e8a252faecf28ccebade999e734ab92582.tar.bz2 otp-210665e8a252faecf28ccebade999e734ab92582.zip | |
Add nopush TCP socket option
This translates to TCP_CORK on Linux and TCP_NOPUSH on
BSD.
In effect, this acts as super-Nagle: no partial TCP segments
are sent out until this option is turned off. Once turned off,
all accumulated unsent data is sent out immediately. The latter
is *not* the case on OSX, hence the implementation ignores
"nopush" on OSX to reduce confusion.
Diffstat (limited to 'erts/emulator')
| -rw-r--r-- | erts/emulator/drivers/common/inet_drv.c | 30 |
1 files changed, 30 insertions, 0 deletions
diff --git a/erts/emulator/drivers/common/inet_drv.c b/erts/emulator/drivers/common/inet_drv.c index 7f20477363..c13ceb14ad 100644 --- a/erts/emulator/drivers/common/inet_drv.c +++ b/erts/emulator/drivers/common/inet_drv.c @@ -812,6 +812,7 @@ static size_t my_strnlen(const char *s, size_t maxlen) #define INET_OPT_PKTOPTIONS 45 /* IP(V6)_PKTOPTIONS get ancillary data */ #define INET_OPT_TTL 46 /* IP_TTL */ #define INET_OPT_RECVTTL 47 /* IP_RECVTTL ancillary data */ +#define TCP_OPT_NOPUSH 48 /* super-Nagle, aka TCP_CORK */ /* SCTP options: a separate range, from 100: */ #define SCTP_OPT_RTOINFO 100 #define SCTP_OPT_ASSOCINFO 101 @@ -955,6 +956,12 @@ static size_t my_strnlen(const char *s, size_t maxlen) #endif +#if defined(TCP_CORK) +#define INET_TCP_NOPUSH TCP_CORK +#elif defined(TCP_NOPUSH) && !defined(__DARWIN__) +#define INET_TCP_NOPUSH TCP_NOPUSH +#endif + #define BIN_REALLOC_MARGIN(x) ((x)/4) /* 25% */ /* The general purpose sockaddr */ @@ -6532,6 +6539,19 @@ static int inet_set_opts(inet_descriptor* desc, char* ptr, int len) (long)desc->port, desc->s, ival)); break; + case TCP_OPT_NOPUSH: +#if defined(INET_TCP_NOPUSH) + proto = IPPROTO_TCP; + type = INET_TCP_NOPUSH; + DEBUGF(("inet_set_opts(%ld): s=%d, t=%d TCP_NOPUSH=%d\r\n", + (long)desc->port, desc->s, type, ival)); + break; +#else + /* inet_fill_opts always returns a value for this option, + * so we need to ignore it if not implemented, just in case */ + continue; +#endif + #if defined(HAVE_MULTICAST_SUPPORT) && defined(IPPROTO_IP) case UDP_OPT_MULTICAST_TTL: @@ -7693,6 +7713,16 @@ static ErlDrvSSizeT inet_fill_opts(inet_descriptor* desc, proto = IPPROTO_TCP; type = TCP_NODELAY; break; + case TCP_OPT_NOPUSH: +#if defined(INET_TCP_NOPUSH) + proto = IPPROTO_TCP; + type = INET_TCP_NOPUSH; + break; +#else + *ptr++ = opt; + put_int32(0, ptr); + continue; +#endif #if defined(HAVE_MULTICAST_SUPPORT) && defined(IPPROTO_IP) case UDP_OPT_MULTICAST_TTL: |