e057f8367c
Let's just see on a diagram how the receiver can detect that the window is large enough for the remote sender to fill the link. Here it seems that a first criterion is that data are accumulating in the rxbuf, indicating that the next hop doesn't consume them fast enough. On the diagram it's visible when blue arrows (incoming data) are more frequent than the magenta ones on average (outgoing data), which happens when silence moments are less frequent and don't allow the reader to catch up. It's also visible that there are two phases alternating in the transfer: - measure round trip time (i.e. how long it takes to restart sending after a WU was sent after a long silence) - measure the lowest rxbuf size during the previous round trip It's worth noting that a window size change only has *observable* effect after two RTT: the first RTT is to restart sending (opening or enlarging the window), the second RTT to measure the lowest rxbuf size over the period. By turning the advertised window into an offset and comparing it to the received quantity, it's possible to measure the RTT of the whole chain (including the client possibly producing the data). Note that when multiple streams compete for BW this can become tricky. Limiting the window to available buffers and counting the number of sending streams on a connection could work (i.e. split total buffers into 1+#senders, first one being used for tx). |
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.. | ||
design-thoughts | ||
internals | ||
lua-api | ||
51Degrees-device-detection.txt | ||
DeviceAtlas-device-detection.txt | ||
HAProxyCommunityEdition_60px.png | ||
SOCKS4.protocol.txt | ||
SPOE.txt | ||
WURFL-device-detection.txt | ||
acl.fig | ||
coding-style.txt | ||
configuration.txt | ||
cookie-options.txt | ||
gpl.txt | ||
haproxy.1 | ||
intro.txt | ||
lgpl.txt | ||
linux-syn-cookies.txt | ||
lua.txt | ||
management.txt | ||
netscaler-client-ip-insertion-protocol.txt | ||
network-namespaces.txt | ||
peers-v2.0.txt | ||
peers.txt | ||
proxy-protocol.txt | ||
queuing.fig | ||
regression-testing.txt | ||
seamless_reload.txt |