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| author | Corinna Vinschen <corinna@vinschen.de> | 2014-11-20 08:29:31 +0000 |
|---|---|---|
| committer | Corinna Vinschen <corinna@vinschen.de> | 2014-11-20 08:29:31 +0000 |
| commit | f70b9c32d5d5b09479b4087bb64f4b95c9821704 (patch) | |
| tree | 4c335c083dcc6f7fc52f6ced4fae0f948d2c66b1 | |
| parent | 5c6a0f3117811cf11b98b471503e02fdc37f96f2 (diff) | |
| download | cygnal-f70b9c32d5d5b09479b4087bb64f4b95c9821704.tar.gz cygnal-f70b9c32d5d5b09479b4087bb64f4b95c9821704.tar.bz2 cygnal-f70b9c32d5d5b09479b4087bb64f4b95c9821704.zip | |
* net.cc (fdsock): Change default values for socket buffers on 32 bit
to fix performance on 10Gb networks.
| -rw-r--r-- | winsup/cygwin/ChangeLog | 5 | ||||
| -rw-r--r-- | winsup/cygwin/net.cc | 11 |
2 files changed, 14 insertions, 2 deletions
diff --git a/winsup/cygwin/ChangeLog b/winsup/cygwin/ChangeLog index c8419f46c..46cd4c3fa 100644 --- a/winsup/cygwin/ChangeLog +++ b/winsup/cygwin/ChangeLog @@ -1,3 +1,8 @@ +2014-11-20 Iuliu Rus <rus.iuliu@gmail.com> + + * net.cc (fdsock): Change default values for socket buffers on 32 bit + to fix performance on 10Gb networks. + 2014-11-17 Corinna Vinschen <corinna@vinschen.de> * uinfo.cc (pwdgrp::fetch_account_from_windows): Allow fetching of diff --git a/winsup/cygwin/net.cc b/winsup/cygwin/net.cc index 8ff88ba11..5c4959bdf 100644 --- a/winsup/cygwin/net.cc +++ b/winsup/cygwin/net.cc @@ -621,13 +621,20 @@ fdsock (cygheap_fdmanip& fd, const device *dev, SOCKET soc) this is no problem on 64 bit. So we set the default buffer size to the default values in current 3.x Linux versions. + NOTE 3. Setting the window size to 65535 results in extremely bad + performance for apps that send data in multiples of Kb, as they + eventually end up sending 1 byte on the network and naggle + delay + ack kicks in. For example, iperf on a 10Gb network gives only 10 + Mbits/sec with a 65535 send buffer. We want this to be a multiple + of 1k, but since 64k breaks WSADuplicateSocket we use 63Kb. + (*) Maximum normal TCP window size. Coincidence? */ #ifdef __x86_64__ ((fhandler_socket *) fd)->rmem () = 212992; ((fhandler_socket *) fd)->wmem () = 212992; #else - ((fhandler_socket *) fd)->rmem () = 65535; - ((fhandler_socket *) fd)->wmem () = 65535; + ((fhandler_socket *) fd)->rmem () = 64512; + ((fhandler_socket *) fd)->wmem () = 64512; #endif if (::setsockopt (soc, SOL_SOCKET, SO_RCVBUF, (char *) &((fhandler_socket *) fd)->rmem (), sizeof (int))) |