Slide 1
MySQL Benchmark Techniques
June 27, 2012Zhang Lu Sr. Operations Architect
[email protected] dollar questionsWhy benchmarking is
important?Benchmarking is the study of a company or organization
that excels in all aspects of its achievements, then using the data
that is collected to improve the performance of their own
companyWhat is performance?Performance is your customers happiness
AOL PowerPoint Template | ConfidentialBenchmark
typesPre-productionresearchPost-production New hardware rolloutNew
software (server) rolloutSchema changes (tuning)Configuration
changes (tuning)
AOL PowerPoint Template | ConfidentialThe stepsClone production
databaseCatch production trafficReplay (real time or
offline)Comparison and draw conclusion
AOL PowerPoint Template | ConfidentialCatch production traffic
tcpdumpUse tcpdump to capture TCP packets to/from MySQL server
portpt-query-digest to parse tcpdump outputProsNo interruption to
applicationEasy to get startedConsIt takes time to parse the
fileNot easy to replay in real timeNo information of current DB
name at the time of request AOL PowerPoint Template |
ConfidentialCatch production traffic MySQL ProxySetup mysqlproxy to
use production DB as backendModify lua script to save incoming
requests along with request time (offset), response time,
etc.Bounce application to use mysqlproxy port instead of MySQL
portProsFlexibleReal time replay is possibleConsAdditional process
needs to be setup (mysqlproxy)Requires some understanding of LUA
language AOL PowerPoint Template | ConfidentialReplayTrue
production replaySame interval between establishing new
connectionsSame interval between each requestOnly difference is the
response time of each requestStress testNo wait between each
requestAdjust interval between new connectionsReplay each set of
files multiple times with overlaps
AOL PowerPoint Template | ConfidentialUsing tcpdump and
pt-query-digesttcpdump -s 65535 -x -nn -q -tttt -i any -c 9000000
port 3306Packet size 65535 (-s)Print each packet in HEX (-x)Do not
convert protocol and port to name (-nn)Quiet less protocol
information (-q)Print timestamp in default format (-tttt)Any
interface (NIC) (-i)Capture 9000000 packets and exit (-c)Only
capture traffic in/out port 3306pt-query-digest --type=tcpdump
--watch-server=10.10.10.123:3306 --print --no-reportMust specify
IP:PORT if your DB is not running on 3306Use nc to stream data to
another host, either save for later use or just pipe to
pt-query-digest
AOL PowerPoint Template | ConfidentialUsing tcpdump and
pt-query-digest - contBefore replaying, need to split the output
from pt-query-digestSplit query into different files based on
client IP and portReformat meta data in the form that the replay
script can understand
AOL PowerPoint Template | Confidential# Time: 120427
11:07:20.908902# Client: 172.19.160.8:48366# Thread_id: 4294967305#
Query time: 0.000154 Lock_time: 0.000000 Rows_sent: 0
Rows_examined: 0SELECT * FROM my_table;# Time: 120427
11:07:20.910313# Client: 172.19.160.8:48366# Thread_id: 4294967305#
Query_time: 0.000454 Lock_time: 0.000000 Rows_sent: 0
Rows_examined: 0SELECT * FROM my_table2;Using mysqlproxy -
setupConfiguration file AOL PowerPoint Template |
Confidential[mysql-proxy]log-file =
/var/log/mysql-proxy.loglog-level =
messageproxy-address=:4040proxy-backend-addresses=dbslab-mtc02.ops.aol.com:3406admin-address
= 127.0.0.1:4041admin-username = prootadmin-password =
padminadmin-lua-script =
/var/lib/mysql-proxy/lua/admin.luakeepalive =
trueproxy-lua-script=/var/lib/mysql-proxy/lua/proxy/myproxy.luaUsing
mysqlproxy lua script Loaded for each connection requestCan be
updated on the flyExternal modules can be loadedMySQL DB requests
is sequential per connectionIt is possible to send the query to
another connection other than production, but that means the client
response time is doubledManipulate incoming requests before send to
the serverManipulate result set before send back to the client
AOL PowerPoint Template | ConfidentialUsing mysqlproxy lua
script functionsread_auth_result()
AOL PowerPoint Template | Confidentialfunction
read_auth_result(auth) local time = os.time() local state =
auth.packet:byte() con_time = time if state ==
proxy.MYSQLD_PACKET_OK then myvars.file = proxy.global.file_base ..
"." .. time .. "." .. proxy.connection.server['thread_id'];
myvars.fh = io.open(myvars.file, "a"); if
proxy.connection.client.default_db ~= '' then query_id = query_id +
1 myvars.fh:write("### Start Time Offset=0 Query Time=0 Response
Time=0 Query ID=" .. query_id .. " Username=" ..
proxy.connection.server['username'] .. "\nUSE " ..
proxy.connection.client.default_db .. "\n### End\n")
myvars.fh:flush() end endendUsing mysqlproxy lua script functions
(contd)read_query() AOL PowerPoint Template | Confidentialfunction
read_query( packet ) query = packet:sub(2) q_time = os.time() -
con_time myvars.query= query if (string.byte(packet) ==
proxy.COM_QUIT) then proxy.global.type = proxy.MYSQLD_PACKET_OK
myvars.fh:write("### Disconnected\n") myvars.fh:close() return
proxy.PROXY_SEND_RESULT elseif string.byte(packet) ==
proxy.COM_INIT_DB then query_id = query_id + 1 myvars.fh:write("###
Start Time Offset=0 Query Time=0 Response Time=0 Query ID=" ..
query_id .. " Username=" .. proxy.connection.server['username'] ..
"\nUSE " .. query .. "\n### End\n") return elseif
string.byte(packet) == proxy.COM_QUERY then proxy.queries:append(1,
string.char(proxy.COM_QUERY) .. query, { resultset_is_needed = true
} ) return proxy.PROXY_SEND_QUERY endend Using mysqlproxy lua
script functions (contd)read_query_result() AOL PowerPoint Template
| Confidentialfunction read_query_result(inj) -- filter out those
SHOW commands -- both inj.query_time and inj.response_time are in
micro seconds, print using milli seconds if
string.find(string.upper(myvars.query), '^SHOW ') then return end
query_id = query_id + 1 header = "### Start Time Offset=" .. q_time
.. " Query Time=" .. (inj.query_time / 1000) .. " Response Time="
.. (inj.response_time / 1000) .. " Query ID=" .. query_id .. "\n"
myvars.fh:write(header) myvars.fh:write(myvars.query .. "\n###
End\n")
myvars.fh:flush()endReferencehttp://dev.mysql.com/doc/refman/5.5/en/mysql-proxy-scripting-structures.html
ReplayUsing any language that can talk to MySQL serverMain thread
watches the lua generated filesCollect all files in the log
directory and sort by created timestampWhen the wait time is up
(delta between the timestamps), which is optional, an new
connection is establishedEach file is processed over one
connectionReplay thread Sends the requests in file to the server
based on the interval between each captured queries
(optional)Record query ID along with response time for analysis
AOL PowerPoint Template | ConfidentialCompare Overall DB time
AOL PowerPoint Template | ConfidentialCompare Update DB time AOL
PowerPoint Template | Confidential
