From: Nick Mathewson <nickm@torproject.org>
Date: Wed, 4 Aug 2010 19:44:08 +0000 (-0400)
Subject: Add an interface to expose min_share in ratelimiting groups
X-Git-Tag: release-2.0.6-rc~14
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=6ae53d676242227bc199c69de9244d6c3599ab44;p=libevent

Add an interface to expose min_share in ratelimiting groups
---

diff --git a/bufferevent_ratelim.c b/bufferevent_ratelim.c
index afae2e3a..cb8a3bf5 100644
--- a/bufferevent_ratelim.c
+++ b/bufferevent_ratelim.c
@@ -646,6 +646,14 @@ bufferevent_rate_limit_group_set_cfg(
 	return 0;
 }
 
+int
+bufferevent_rate_limit_group_set_min_share(
+	struct bufferevent_rate_limit_group *g,
+	size_t share)
+{
+	g->min_share = share;
+	return 0;
+}
 
 void
 bufferevent_rate_limit_group_free(struct bufferevent_rate_limit_group *g)
diff --git a/include/event2/bufferevent.h b/include/event2/bufferevent.h
index 55e44f9c..b87f3a29 100644
--- a/include/event2/bufferevent.h
+++ b/include/event2/bufferevent.h
@@ -626,6 +626,26 @@ struct bufferevent_rate_limit_group *bufferevent_rate_limit_group_new(
 int bufferevent_rate_limit_group_set_cfg(
 	struct bufferevent_rate_limit_group *,
 	const struct ev_token_bucket_cfg *);
+
+/**
+   Change the smallest quantum we're willing to allocate to any single
+   bufferevent in a group for reading or writing at a time.
+
+   The rationale is that, because of TCP/IP protocol overheads and kernel
+   behavior, if a rate-limiting group is so tight on bandwidth that you're
+   only willing to send 1 byte per tick per bufferevent, you might instead
+   want to batch up the reads and writes so that you send N bytes per
+   1/N of the bufferevents (chosen at random) each tick, so you still wind
+   up send 1 byte per tick per bufferevent on average, but you don't send
+   so many tiny packets.
+
+   The default min-share is currently 64 bytes.
+
+   Returns 0 on success, -1 on faulre.
+ */
+int bufferevent_rate_limit_group_set_min_share(
+	struct bufferevent_rate_limit_group *, size_t);
+
 /**
    Free a rate-limiting group.  The group must have no members when
    this function is called.