##  Copyright (c) 2007-2008 Facebook
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##  Licensed under the Apache License, Version 2.0 (the "License");
##  you may not use this file except in compliance with the License.
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##      http://www.apache.org/licenses/LICENSE-2.0
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##  distributed under the License is distributed on an "AS IS" BASIS,
##  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
##  See the License for the specific language governing permissions and
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## See accompanying file LICENSE or visit the Scribe site at:
## http://developers.facebook.com/scribe/

One of the common problems we face when running scribe is that when multiple
scribe servers(senders) are forwarding messages to a single scribe server(receiver)
some times the receiver cannot keep up and asks the remote servers to backoff
by sending a TRY_LATER.
This test is used to simulate that behavior so that we can study it and
improve the way scribe senders backoff. In this test we basically try to
"hammer" a scribe receiver.

You will need 3 servers: 2 will act as senders and 1 as receiver

IMPORTANT: substitute "put_your_receiving_server_here" in hammersource.conf
appropriately with you receiving server

Follow the steps in order
1. On the 1st sender do
$ cd scribe/test/simulatebackoff
$ scribed -c hammersource.conf -p 1463     # start the scribe server 1
On another terminal window do
$ sudo php new.superstress.php  # create scribe clients and send to server 2

2. On the 2nd sender do
$ cd scribe/test/simulatebackoff
$ scribed -c hammersource.conf -p 1463    # start the scribe server 2
On another terminal window do
$ sudo php new.superstress.php  # create scribe clients and send to server 2

3. Wait a few minutes and let the two servers buffer messages to local disk
for a while. For consistency you may wait for new.superstress.php to finish

4. On the scribe receiver
$ sudo rm -rf /tmp/defaultprimary /tmp/defaultsecondary /tmp/hammerprimary
/tmp/hammersecondary
$ cd scribe/test/simulatebackoff
$ scribed hammersink.conf     # start the scribe receiver

5. Use $sudo scribe_ctrl counters 1463 on the machines to get basic counters.

6. Use some monitoring system like ganglia to study the network sent/received
bytes, memory usages and disk

7. Verify that all messages sent were received. Note that you cannot use
resultchecker for this because two senders are used.