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diff --git a/src/ceph/doc/dev/blkin.rst b/src/ceph/doc/dev/blkin.rst deleted file mode 100644 index 8e0320f..0000000 --- a/src/ceph/doc/dev/blkin.rst +++ /dev/null @@ -1,167 +0,0 @@ -========================= - Tracing Ceph With BlkKin -========================= - -Ceph can use Blkin, a library created by Marios Kogias and others, -which enables tracking a specific request from the time it enters -the system at higher levels till it is finally served by RADOS. - -In general, Blkin implements the Dapper_ tracing semantics -in order to show the causal relationships between the different -processing phases that an IO request may trigger. The goal is an -end-to-end visualisation of the request's route in the system, -accompanied by information concerning latencies in each processing -phase. Thanks to LTTng this can happen with a minimal overhead and -in realtime. The LTTng traces can then be visualized with Twitter's -Zipkin_. - -.. _Dapper: http://static.googleusercontent.com/media/research.google.com/el//pubs/archive/36356.pdf -.. _Zipkin: http://zipkin.io/ - - -Installing Blkin -================ - -You can install Markos Kogias' upstream Blkin_ by hand.:: - - cd blkin/ - make && make install - -or build distribution packages using DistroReadyBlkin_, which also comes with -pkgconfig support. If you choose the latter, then you must generate the -configure and make files first.:: - - cd blkin - autoreconf -i - -.. _Blkin: https://github.com/marioskogias/blkin -.. _DistroReadyBlkin: https://github.com/agshew/blkin - - -Configuring Ceph with Blkin -=========================== - -If you built and installed Blkin by hand, rather than building and -installing packages, then set these variables before configuring -Ceph.:: - - export BLKIN_CFLAGS=-Iblkin/ - export BLKIN_LIBS=-lzipkin-cpp - -Since there are separate lttng and blkin changes to Ceph, you may -want to configure with something like:: - - ./configure --with-blkin --without-lttng --with-debug - - -Testing Blkin -============= - -It's easy to test Ceph's Blkin tracing. Let's assume you don't have -Ceph already running, and you compiled Ceph with Blkin support but -you did't install it. Then launch Ceph with the ``vstart.sh`` script -in Ceph's src directgory so you can see the possible tracepoints.:: - - cd src - OSD=3 MON=3 RGW=1 ./vstart.sh -n - lttng list --userspace - -You'll see something like the following::: - - UST events: - ------------- - PID: 8987 - Name: ./ceph-osd - zipkin:timestamp (loglevel: TRACE_WARNING (4)) (type: tracepoint) - zipkin:keyval (loglevel: TRACE_WARNING (4)) (type: tracepoint) - ust_baddr_statedump:soinfo (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) - - PID: 8407 - Name: ./ceph-mon - zipkin:timestamp (loglevel: TRACE_WARNING (4)) (type: tracepoint) - zipkin:keyval (loglevel: TRACE_WARNING (4)) (type: tracepoint) - ust_baddr_statedump:soinfo (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) - - ... - -Next, stop Ceph so that the tracepoints can be enabled.:: - - ./stop.sh - -Start up an LTTng session and enable the tracepoints.:: - - lttng create blkin-test - lttng enable-event --userspace zipkin:timestamp - lttng enable-event --userspace zipkin:keyval - lttng start - -Then start up Ceph again.:: - - OSD=3 MON=3 RGW=1 ./vstart.sh -n - -You may want to check that ceph is up.:: - - ./ceph status - -Now put something in usin rados, check that it made it, get it back, and remove it.:: - - ./rados mkpool test-blkin - ./rados put test-object-1 ./vstart.sh --pool=test-blkin - ./rados -p test-blkin ls - ./ceph osd map test-blkin test-object-1 - ./rados get test-object-1 ./vstart-copy.sh --pool=test-blkin - md5sum vstart* - ./rados rm test-object-1 --pool=test-blkin - -You could also use the example in ``examples/librados/`` or ``rados bench``. - -Then stop the LTTng session and see what was collected.:: - - lttng stop - lttng view - -You'll see something like::: - - [13:09:07.755054973] (+?.?????????) scruffy zipkin:timestamp: { cpu_id = 5 }, { trace_name = "Main", service_name = "MOSDOp", port_no = 0, ip = "0.0.0.0", trace_id = 7492589359882233221, span_id = 2694140257089376129, parent_span_id = 0, event = "Message allocated" } - [13:09:07.755071569] (+0.000016596) scruffy zipkin:keyval: { cpu_id = 5 }, { trace_name = "Main", service_name = "MOSDOp", port_no = 0, ip = "0.0.0.0", trace_id = 7492589359882233221, span_id = 2694140257089376129, parent_span_id = 0, key = "Type", val = "MOSDOp" } - [13:09:07.755074217] (+0.000002648) scruffy zipkin:keyval: { cpu_id = 5 }, { trace_name = "Main", service_name = "MOSDOp", port_no = 0, ip = "0.0.0.0", trace_id = 7492589359882233221, span_id = 2694140257089376129, parent_span_id = 0, key = "Reqid", val = "client.4126.0:1" } - ... - - -Install Zipkin -=============== -One of the points of using Blkin is so that you can look at the traces -using Zipkin. Users should run Zipkin as a tracepoints collector and -also a web service, which means users need to run three services, -zipkin-collector, zipkin-query and zipkin-web. - -Download Zipkin Package:: - - wget https://github.com/twitter/zipkin/archive/1.1.0.tar.gz - tar zxf 1.1.0.tar.gz - cd zipkin-1.1.0 - bin/collector cassandra & - bin/query cassandra & - bin/web & - -Check Zipkin:: - - bin/test - Browse http://${zipkin-web-ip}:8080 - - -Show Ceph's Blkin Traces in Zipkin-web -====================================== -Blkin provides a script which translates lttng result to Zipkin -(Dapper) semantics. - -Send lttng data to Zipkin:: - - python3 babeltrace_zipkin.py ${lttng-traces-dir}/${blkin-test}/ust/uid/0/64-bit/ -p ${zipkin-collector-port(9410 by default)} -s ${zipkin-collector-ip} - -Example:: - - python3 babeltrace_zipkin.py ~/lttng-traces-dir/blkin-test-20150225-160222/ust/uid/0/64-bit/ -p 9410 -s 127.0.0.1 - -Check Ceph traces on webpage:: - - Browse http://${zipkin-web-ip}:8080 - Click "Find traces" |