SEO

I hope that my contacting you is not an imposition in any way.

My name is Koki Takeda.

This time, I made the php program using MySQL.

The child process is generated in the program, and MySQL query
are transmitted two or more times in the child process. That's
my problem.

There is difficultly both executions in a present environment
though I thought about the following two solutions by
investigating.

I will inform the following of details. Please teach some
solutions.

And, please contact me when there are lack information etc.

I would be very happy to hear from you.

------------------------------------------
$B"#(B Facts

OS: SunOS xxx 5.8 Generic_108528-23 sun4u sparc
SUNW,UltraAX-i2 (Solaris 8)
php: 4.3.9
Mysql: Ver 4.0.12-standard for sun-solaris2.8 on sparc


$B"#(B Content of processing

In the made php program (A temporary name: test.php), it
transmits repeating MySQL query (select,insert) according to
MySQL function mysql_query.

And, test.php forking does the process, and operates at the
same time five child processes.
MySQL query is transmitted about 2500 times in all child
process total.

I will explain the outline of the program and the outline of
the program flow as follows.

$B!c(BOutline of test.php program$B!d(B

It is processing that forwards an arbitrary file to
another server.

$B!c(BOutline of test.php program flow$B!d(B

Start

Query execution to acquire file list to be transmitted
(real environment: About 60 records)
mysql_query (select)

Ceri execution to acquire server list(real environment:
Five records)
mysql_query (select)

Beginning of loop1(loop for a few minutes of server) {

It is a fork as for the process.

if Fork failure {

Error processing

} elseif parent process {

Process ID backup

} else { child process

Beginning of loop2(loop for a few minutes of file
for forwarding) {

Ceri execution that judges forwarding
mysql_query (select)

if It is not an object of forwarding
(Forwarded it. ) {

Ceri execution of log writing
mysql_query (insert)

Continuance of loop2
$B!!!!!!!!!!!!!!!!(B}

Forwarding execution

End of loop2
}

End of loop1

Processing that waits for end of all child processes

End


$B"#(B symptom

Processing ends normally in case of almost.
However, in rare cases, it doesn't return from the
mysql_query processing after mysql_query is called about
200-250 times in total by all child process processing, and
processing stops.

SQL sentence that doesn't return from the mysql_query
processing is as follows.

$B!&(Bselect updated from table_name_1 where code = 98

$B!&(Binsert into table_name_2 ( field_name_1,field_name_2,$B!!!!(B
field_name_3,field_name_4,field_name_5 ) values ( '1', '',
'', 1,'XX#1(doc01)(192.168.1.100)$B!'(BThe copy processing was
skipped.(aaa.xxx) ' )

And Mysqld is done while having started while this symptom
is occurring.
And, other Ceri can be executed.

Nonw, when this symptom occurs, kill does me parent process
and 5 child processes now.


$B"#(B Idea of solution

It was able to be confirmed that the following errors might
occur when test.php was being executed. $B!!(BTherefore, I
judged that the buffer might been filled.

$B!c(BError message$B!d(B
Malformed packet

Then, I considered the idea of the following two solutions.
However, both influences that it has on other programs are
large, and time is required for the verification.
Therefore, I am looking for other solutions.

$B!c(BIdea of solution$B!d(B
(1)After mysql_query is executed, the processing of the
flush of query cash is added.
(2)Upgrade of mysql


$B"#(B Content of question

Based on above, I want to make the following question.

$B!&(BIs there a case similar to this symptom?

$B!&(BHow was this symptom canceled when there was a similar
case?

$B!&(BAdditionally, does another have the thought solution?

Hi Koki,

You have to re- establish the database connection in each child process.
Otherwise the packets get mangled and you get the errors you're seeing.

Koki Takeda wrote:
> I hope that my contacting you is not an imposition in any way.
>
> My name is Koki Takeda.
>
> This time, I made the php program using MySQL.
>
> The child process is generated in the program, and MySQL query
> are transmitted two or more times in the child process. That's
> my problem.
>
> There is difficultly both executions in a present environment
> though I thought about the following two solutions by
> investigating.
>
> I will inform the following of details. Please teach some
> solutions.
>
> And, please contact me when there are lack information etc.
>
> I would be very happy to hear from you.
>
> ------------------------------------------
> â–* Facts
>
> OS: SunOS xxx 5.8 Generic_108528-23 sun4u sparc
> SUNW,UltraAX-i2 (Solaris 8)
> php: 4.3.9
> Mysql: Ver 4.0.12-standard for sun-solaris2.8 on sparc
>
>
> â–* Content of processing
>
> In the made php program (A temporary name: test.php), it
> transmits repeating MySQL query (select,insert) according to
> MySQL function mysql_query.
>
> And, test.php forking does the process, and operates at the
> same time five child processes.
> MySQL query is transmitted about 2500 times in all child
> process total.
>
> I will explain the outline of the program and the outline of
> the program flow as follows.
>
> ＜Outline of test.php program＞
>
> It is processing that forwards an arbitrary file to
> another server.
>
> ＜Outline of test.php program flow＞
>
> Start
>
> Query execution to acquire file list to be transmitted
> (real environment: About 60 records)
> mysql_query (select)
>
> Ceri execution to acquire server list(real environment:
> Five records)
> mysql_query (select)
>
> Beginning of loop1(loop for a few minutes of server) {
>
> It is a fork as for the process.
>
> if Fork failure {
>
> Error processing
>
> } elseif parent process {
>
> Process ID backup
>
> } else { child process
>
> Beginning of loop2(loop for a few minutes of file
> for forwarding) {
>
> Ceri execution that judges forwarding
> mysql_query (select)
>
> if It is not an object of forwarding
> (Forwarded it. ) {
>
> Ceri execution of log writing
> mysql_query (insert)
>
> Continuance of loop2
> 　　　　　　　　}
>
> Forwarding execution
>
> End of loop2
> }
>
> End of loop1
>
> Processing that waits for end of all child processes
>
> End
>
>
> â–* symptom
>
> Processing ends normally in case of almost.
> However, in rare cases, it doesn't return from the
> mysql_query processing after mysql_query is called about
> 200-250 times in total by all child process processing, and
> processing stops.
>
> SQL sentence that doesn't return from the mysql_query
> processing is as follows.
>
> ・select updated from table_name_1 where code = 98
>
> ・insert into table_name_2 ( field_name_1,field_name_2,　　
> field_name_3,field_name_4,field_name_5 ) values ( '1', '',
> '', 1,'XX#1(doc01)(192.168.1.100)：The copy processing was
> skipped.(aaa.xxx) ' )
>
> And Mysqld is done while having started while this symptom
> is occurring.
> And, other Ceri can be executed.
>
> Nonw, when this symptom occurs, kill does me parent process
> and 5 child processes now.
>
>
> â–* Idea of solution
>
> It was able to be confirmed that the following errors might
> occur when test.php was being executed. 　Therefore, I
> judged that the buffer might been filled.
>
> ＜Error message＞
> Malformed packet
>
> Then, I considered the idea of the following two solutions.
> However, both influences that it has on other programs are
> large, and time is required for the verification.
> Therefore, I am looking for other solutions.
>
> ＜Idea of solution＞
> (1)After mysql_query is executed, the processing of the
> flush of query cash is added.
> (2)Upgrade of mysql
>
>
> â–* Content of question
>
> Based on above, I want to make the following question.
>
> ・Is there a case similar to this symptom?
>
> ・How was this symptom canceled when there was a similar
> case?
>
> ・Additionally, does another have the thought solution?
>
>
>
>