First of all I must say that I have somewhat basic knowledge of sql server and with that I'm trying to figure out how to resolve a deadlock.
I ran dbcc traceon (1204, -1), executed the culprit code and finally executed the xp_readerrorlog stored proc which gave me the following output:
Deadlock encountered .... Printing deadlock information
Wait-for graph
NULL
Node:1
OBJECT: 9:1093578934:0 CleanCnt:2 Mode:IX Flags: 0x1
Grant List 2:
Grant List 3:
Owner:0x000000008165A780 Mode: IX Flg:0x40 Ref:2 Life:02000000 SPID:57 ECID:0 XactLockInfo: 0x0000000082F00EC0
SPID: 57 ECID: 0 Statement Type: EXECUTE Line #: 1
Input Buf: RPC Event: Proc [Database Id = 9 Object Id = 1877581727]
Requested by:
ResType:LockOwner Stype:'OR'Xdes:0x0000000082E02E80 Mode: S SPID:56 BatchID:0 ECID:0 TaskProxy:(0x00000000826EE538) Value:0x81a6f9c0 Cost:(0/1492)
NULL
Node:2
APPLICATION: 9:0:[Proligent Analytics]:(6ff56412) CleanCnt:2 Mode:X Flags: 0x5
Grant List 2:
Owner:0x000000008165DE40 Mode: X Flg:0x40 Ref:1 Life:00000000 SPID:56 ECID:0 XactLockInfo: 0x0000000082E02EC0
SPID: 56 ECID: 0 Statement Type: OPEN CURSOR Line #: 27
Input Buf: RPC Event: Proc [Database Id = 9 Object Id = 1966630049]
Requested by:
ResType:LockOwner Stype:'OR'Xdes:0x0000000082F00E80 Mode: X SPID:57 BatchID:0 ECID:0 TaskProxy:(0x00000000827B8538) Value:0x83e29d40 Cost:(0/250576)
NULL
Victim Resource Owner:
ResType:LockOwner Stype:'OR'Xdes:0x0000000082E02E80 Mode: S SPID:56 BatchID:0 ECID:0 TaskProxy:(0x00000000826EE538) Value:0x81a6f9c0 Cost:(0/1492)
My problem is that I have no idea how to use this to find out what's going on. I've read that you can get the stored procedure that is getting locked but I don't know how.
Please a few pointers would be appreciated.
Thanks
As #Martin Smith says in his comment: select db_name(9), object_name(1093578934,9), object_name(1966630049,9), object_name(1877581727,9) should give you some of the objects.
Related
I have a async action on my controller that can perform a heavy SQL query depending on user input.
#results = ActiveRecord::Base
.connection
.select_all(query_string)
.map do |record|
Hashie::Mash.new(record)
end
When it happens, the only response I get from the server is
E, [2020-02-05T16:14:04.133233 #59909] ERROR -- : worker=0 PID:60952 timeout (61s > 60s), killing
E, [2020-02-05T16:14:04.159372 #59909] ERROR -- : reaped #<Process::Status: pid 60952 SIGKILL (signal 9)> worker=0
Is there any way I can capture this timeout on the backend, to give the user the correct feedback?
Tried using Timeout::timeout(x) but with no success.
You could add another, shorter timeout yourself and handle the situation before the worker gets killed. Something like this might be a good start:
require 'timeout'
begin
# 5 seconds before the MySQL timeout would kick in
Timeout.timeout(55) do
# have only the slow query in this block
#database_results = ActiveRecord::Base.connection.select_all(query_string)
end
rescue Timeout::Error
# Handle the timeout. Proper error handling depends on your application.
# In a controller you might just want to return an error page, in a
# background worker you might want to record the error in your database.
end
# time to translate the data should not count towards the timeout
#results = #database_results.map { |r| Hashie::Mash.new(r) }
I was running into a memory leak using mathworks' database toolbox with mysql. If I was returning large amounts of data, eventually the I would get an out of memory error running out of java heap space.
I had seen this before and used the com.mysql.jdbc.JDBC4Prepared Statement and com.mysql.jdbc.JDBC4ResultSet driver calls myself. When you do this, you have to be sure to call the close() methods of each of those, or else you have the same problem.
I remembered this today when mathworks shoddy object was hitting heap problems by just exec'ing the same query and fetching the results a few thousand times. It turns out you can see the mysql jdbc objects in the mathworks cursor and resultset objects:
curs = exec(dbConn, sqlStr)
rs = fetch(curs)
curs =
Attributes: []
Data: 0
DatabaseObject: [1x1 database]
RowLimit: 0
SQLQuery: 'xxxxxomitxxxx'
Message: []
Type: 'Database Cursor Object'
ResultSet: [1x1 com.mysql.jdbc.JDBC4ResultSet]
Cursor: [1x1 com.mathworks.toolbox.database.sqlExec]
Statement: [1x1 com.mysql.jdbc.StatementImpl]
Fetch: 0
rs =
Attributes: []
Data: {2497x8 cell}
DatabaseObject: [1x1 database]
RowLimit: 0
SQLQuery: 'xxxxxomitxxxx'
Message: []
Type: 'Database Cursor Object'
ResultSet: [1x1 com.mysql.jdbc.JDBC4ResultSet]
Cursor: [1x1 com.mathworks.toolbox.database.sqlExec]
Statement: [1x1 com.mysql.jdbc.StatementImpl]
Fetch: [1x1 com.mathworks.toolbox.database.fetchTheData]
The OP wrote:
well, by closing the mysql jdbc objects yourself after every fetch you can fix the problem, and not have to extract all of the mathworks code you've used everywhere:
rs.Statement.close()
rs.ResultSet.close()
I am trying to connect to a mysql server using LuaSql via a mysql proxy. I try to execute a simple program (db.lua):
require("luasql.mysql")
local _sqlEnv = assert(luasql.mysql())
local _con = nil
function read_auth(auth)
local host, port = string.match(proxy.backends[1].address, "(.*):(.*)")
_con = assert(_sqlEnv:connect( "db_name", "username", "password", "hostname", "3306"))
end
function disconnect_client()
assert(_con:close())
end
function read_query(packet)
local cur = con:execute("select * from t1")
myTable = {}
row = cur:fetch(myTable, "a")
print(myTable.id,myTable.user)
end
This code executes well when I execute it without mysql-proxy. When I am connecting with mysql-proxy, the error-log displays these errors:
mysql.lua:8: bad argument #1 to 'insert' (table expected, got nil)
db.lua:1: loop or previous error loading module 'luasql.mysql'
mysql.lua is a default file of LuaSql:
---------------------------------------------------------------------
-- MySQL specific tests and configurations.
-- $Id: mysql.lua,v 1.4 2006/01/25 20:28:30 tomas Exp $
---------------------------------------------------------------------
QUERYING_STRING_TYPE_NAME = "binary(65535)"
table.insert (CUR_METHODS, "numrows")
table.insert (EXTENSIONS, numrows)
---------------------------------------------------------------------
-- Build SQL command to create the test table.
---------------------------------------------------------------------
local _define_table = define_table
function define_table (n)
return _define_table(n) .. " TYPE = InnoDB;"
end
---------------------------------------------------------------------
-- MySQL versions 4.0.x do not implement rollback.
---------------------------------------------------------------------
local _rollback = rollback
function rollback ()
if luasql._MYSQLVERSION and string.sub(luasql._MYSQLVERSION, 1, 3) == "4.0" then
io.write("skipping rollback test (mysql version 4.0.x)")
return
else
_rollback ()
end
end
As stated in my previous comment, the error indicates that table.insert (CUR_METHODS, ...) is getting a nil as first arg. Since the first arg is CUR_METHODS, it means that this object CUR_METHODS has not been defined yet. Since this happens near top of the luasql.mysql module, my guess is that the luasql initialization was incomplete, maybe because the mysql DLL was not found. My guess is that the LUA_CPATH does not find the MySQL DLL for luasql, but I'm surprised that you wouldn't get a package error, so something odd is going on. You'll have to dig into the luasql module and C file to figure out why it is not being created.
Update: alternately, update your post to show the output of print("LUA path:", package.path) and print("LUA path:", package.cpath) from your mysql-proxy script and also show the path of folder where luasql is installed and contents of that folder.
Trying to add a comment (in json) to a transaction but keep getting this error: "error: value is type obj, expected int"
bitcoind move acc1 acc2 0.00000002 '{"test":"hi"}'
I was missing the minconf=1 arg value (ie. needed a 1):
bitcoind move acc1 acc2 0.00000002 1 '{"test":"hi"}'
I just downloaded the mysql-proxy and created this script lua (found in Mysql docs):
function read_query(packet)
if string.byte(packet) == proxy.COM_QUERY then
print("QUERY: " .. string.sub(packet, 2))
end
end
This is the command-line I'm using:
mysql-proxy -P localhost:1234 -b localhost:3306 --proxy-lua-script=profile.lua --plugins=proxy
When I run a simple query (like "select * from table1"), this error is reported: "failed: .\lua-scope.c:241: stat(C:...\profile.lua) failed: No error (0)"
Note: If I run mysql-proxy without lua script, no error occurs.
I need to install something to get mysql-proxy and query tracing working?
My environment is Windows 7 Professional x64.
Sorry the bad english.
The error you're getting is caused by --proxy-lua-script pointing to a file that mysql-proxy can't find. Either you've typed the name in wrong, you've typed the path in wrong, or you are expecting it in your CWD and it's not there. Or actually, looking at the entire error a little more closely, it seems possible that mysql-proxy itself sees the file in CWD itself OK, but one of the underlying modules doesn't like it (possibly because mysql-proxy changes the CWD somehow?)
Try saving profile.lua to the root of your C: drive and trying different versions of the option like so:
--proxy-lua-script=c:\profile.lua
--proxy-lua-script=\profile.lua
--proxy-lua-script=/profile.lua
One of those would probably work
simple query log lua script:
require("mysql.tokenizer")
local fh = io.open("/var/log/mysql/proxy.query.log", "a+")
fh:setvbuf('line',4096)
local the_query = "";
local seqno = 0;
function read_query( packet )
if string.byte(packet) == proxy.COM_QUERY then
seqno = seqno + 1
the_query = (string.gsub(string.gsub(string.sub(packet, 2), "%s%s*", ' '), "^%s*(.-)%s*$", "%1"))
fh:write(string.format("%s %09d %09d : %s (%s) -- %s\n",
os.date('%Y-%m-%d %H:%M:%S'),
proxy.connection.server.thread_id,
seqno,
proxy.connection.client.username,
proxy.connection.client.default_db,
the_query))
fh:flush()
return proxy.PROXY_SEND_QUERY
else
query = ""
end
end