This is intended to demonstrate how badly we suck at dealing
with slow clients. It can help users evaluate alternative
fully-buffering reverse proxies, because nginx should not
be the only option.
Update the benchmark README while we're at it
---
test/benchmark/README | 13 +++++++---
test/benchmark/ddstream.ru | 50 ++++++++++++++++++++++++++++++++++++++
2 files changed, 59 insertions(+), 4 deletions(-)
create mode 100644 test/benchmark/ddstream.ru
diff --git a/test/benchmark/README b/test/benchmark/README
index 1d3cdd0..e9b7a41 100644
--- a/test/benchmark/README
+++ b/test/benchmark/README
@@ -42,9 +42,14 @@ The benchmark client is usually httperf.
Another gentle reminder: performance with slow networks/clients
is NOT our problem. That is the job of nginx (or similar).
+== ddstream.ru
+
+Standalone Rack app intended to show how BAD we are at slow clients.
+See usage in comments.
+
== Contributors
-This directory is maintained independently in the "benchmark" branch
-based against v0.1.0. Only changes to this directory (test/benchmarks)
-are committed to this branch although the master branch may merge this
-branch occassionaly.
+This directory is intended to remain stable. Do not make changes
+to benchmarking code which can change performance and invalidate
+results across revisions. Instead, write new benchmarks and update
+coments/documentation as necessary.
diff --git a/test/benchmark/ddstream.ru b/test/benchmark/ddstream.ru
new file mode 100644
index 0000000..b14c973
--- /dev/null
+++ b/test/benchmark/ddstream.ru
@@ -0,0 +1,50 @@
+# This app is intended to test large HTTP responses with or without
+# a fully-buffering reverse proxy such as nginx. Without a fully-buffering
+# reverse proxy, unicorn will be unresponsive when client count exceeds
+# worker_processes.
+#
+# To demonstrate how bad unicorn is at slowly reading clients:
+#
+# # in one terminal, start unicorn with one worker:
+# unicorn -E none -l 127.0.0.1:8080 test/benchmark/ddstream.ru
+#
+# # in a different terminal, start more slow curl processes than
+# # unicorn workers and watch time outputs
+# curl --limit-rate 8K --trace-time -vsN http://127.0.0.1:8080/ >/dev/null &
+# curl --limit-rate 8K --trace-time -vsN http://127.0.0.1:8080/ >/dev/null &
+# wait
+#
+# The last client won't see a response until the first one is done reading
+#
+# nginx note: do not change the default "proxy_buffering" behavior.
+# Setting "proxy_buffering off" prevents nginx from protecting unicorn.
+
+# totally standalone rack app to stream a giant response
+class BigResponse
+ def initialize(bs, count)
+ @buf = "#{bs.to_s(16)}\r\n#{' ' * bs}\r\n"
+ @count = count
+ @res = [ 200,
+ { 'Transfer-Encoding' => -'chunked', 'Content-Type' => 'text/plain' },
+ self
+ ]
+ end
+
+ # rack response body iterator
+ def each
+ (1..@count).each { yield @buf }
+ yield -"0\r\n\r\n"
+ end
+
+ # rack app entry endpoint
+ def call(_env)
+ @res
+ end
+end
+
+# default to a giant (128M) response because kernel socket buffers
+# can be ridiculously large on some systems
+bs = ENV['bs'] ? ENV['bs'].to_i : 65536
+count = ENV['count'] ? ENV['count'].to_i : 2048
+warn "serving response with bs=#{bs} count=#{count} (#{bs*count} bytes)"
+run BigResponse.new(bs, count)
--
EW