0001497: DB Connection Management error using Mysqli

(0001714)
dberry
01-11-07 10:44

Here is an updated test case. Originally I thought the problem was the fact that env.getConnection() did not check to see if connection was closed prior to being handed out, but the problem is deeper than that. You are handing out connections with a total disregard for the concept of a transaction. My recommendation is to do the connection pooling in MysqliModule so that you will not handout connections that are already in use.

Here is the new test case.

$db = mysqli_connect(MYSQL_HOST, MYSQL_USER, MYSQL_PASS, MYSQL_DB, MYSQL_PORT);
$db->autocommit(false);
$db->close();
syslog(LOG_ERR,"Performed First Close.");

$db1 = mysqli_connect(MYSQL_HOST, MYSQL_USER, MYSQL_PASS, MYSQL_DB, MYSQL_PORT);
$db1->autocommit(false);
$db->close();
syslog(LOG_ERR,"Performed Second Close.");

// Now lets do a nested close to break this connection cache.
$db = mysqli_connect(MYSQL_HOST, MYSQL_USER, MYSQL_PASS, MYSQL_DB, MYSQL_PORT);
$db1 = mysqli_connect(MYSQL_HOST, MYSQL_USER, MYSQL_PASS, MYSQL_DB, MYSQL_PORT);
$db1->autocommit(false);
$db->close();
syslog(LOG_ERR,"Performed Third Close.");

$db->autocommit(false);
$db->close();
syslog(LOG_ERR,"Performed Fourth Close.");

(0001715)
dberry
01-11-07 11:23

TYPO in the test case here it is again:

$db = mysqli_connect(MYSQL_HOST, MYSQL_USER, MYSQL_PASS, MYSQL_DB, MYSQL_PORT);
$db->autocommit(false);
$db->close();
syslog(LOG_ERR,"Performed First Close.");

$db1 = mysqli_connect(MYSQL_HOST, MYSQL_USER, MYSQL_PASS, MYSQL_DB, MYSQL_PORT);
$db1->autocommit(false);
$db->close();
syslog(LOG_ERR,"Performed Second Close.");

// Now lets do a nested close to break this connection cache.
$db = mysqli_connect(MYSQL_HOST, MYSQL_USER, MYSQL_PASS, MYSQL_DB, MYSQL_PORT);
$db1 = mysqli_connect(MYSQL_HOST, MYSQL_USER, MYSQL_PASS, MYSQL_DB, MYSQL_PORT);
$db1->autocommit(false);
$db1->close();
syslog(LOG_ERR,"Performed Third Close.");

$db->autocommit(false);
$db->close();
syslog(LOG_ERR,"Performed Fourth Close.");

(0001716)
dberry
01-11-07 11:27

Here is the modified env.getConnection(). It is a removal of the caching logic:

/**
   * Returns the configured database.
   */
  public Connection getConnection(String driver, String url,
                                  String userName, String password)
    throws Exception
  {
    DataSource database = _quercus.getDatabase();

    if (database != null)
      return database.getConnection();

    database = _quercus.findDatabase(driver, url);

    if (userName == null || userName.equals(""))
      return database.getConnection();

    return database.getConnection(userName, password);

  }

(0001720)
nam
01-16-07 10:06

php/1418 ('using closed connection' fixed)

Quercus hands out connections based on the (host, username, password) tuple. PHP scripts tend to open a new connection without closing the previous connection. For most cases, PHP scripts use the new connection exclusively and the race condition where multiple open connections to the same database tuple are actively used is a non-issue for real applications.

(0001778)
nam
03-20-07 10:41

php/1f19

Issue History
Date Modified	Username	Field	Change
12-08-06 05:37	dberry	New Issue
01-11-07 10:44	dberry	Note Added: 0001714
01-11-07 11:23	dberry	Note Added: 0001715
01-11-07 11:27	dberry	Note Added: 0001716
01-16-07 10:06	nam	Note Added: 0001720
01-16-07 10:11	nam	Status	new => assigned
01-16-07 10:11	nam	Assigned To	=> nam
01-16-07 10:11	nam	Status	assigned => closed
01-16-07 10:11	nam	Resolution	open => fixed
01-16-07 10:11	nam	Fixed in Version	=> 3.1.1
03-20-07 10:41	nam	Status	closed => assigned
03-20-07 10:41	nam	Status	assigned => closed
03-20-07 10:41	nam	Note Added: 0001778

Notes
(0001714) dberry 01-11-07 10:44	Here is an updated test case. Originally I thought the problem was the fact that env.getConnection() did not check to see if connection was closed prior to being handed out, but the problem is deeper than that. You are handing out connections with a total disregard for the concept of a transaction. My recommendation is to do the connection pooling in MysqliModule so that you will not handout connections that are already in use. Here is the new test case. $db = mysqli_connect(MYSQL_HOST, MYSQL_USER, MYSQL_PASS, MYSQL_DB, MYSQL_PORT); $db->autocommit(false); $db->close(); syslog(LOG_ERR,"Performed First Close."); $db1 = mysqli_connect(MYSQL_HOST, MYSQL_USER, MYSQL_PASS, MYSQL_DB, MYSQL_PORT); $db1->autocommit(false); $db->close(); syslog(LOG_ERR,"Performed Second Close."); // Now lets do a nested close to break this connection cache. $db = mysqli_connect(MYSQL_HOST, MYSQL_USER, MYSQL_PASS, MYSQL_DB, MYSQL_PORT); $db1 = mysqli_connect(MYSQL_HOST, MYSQL_USER, MYSQL_PASS, MYSQL_DB, MYSQL_PORT); $db1->autocommit(false); $db->close(); syslog(LOG_ERR,"Performed Third Close."); $db->autocommit(false); $db->close(); syslog(LOG_ERR,"Performed Fourth Close.");

(0001715) dberry 01-11-07 11:23	TYPO in the test case here it is again: $db = mysqli_connect(MYSQL_HOST, MYSQL_USER, MYSQL_PASS, MYSQL_DB, MYSQL_PORT); $db->autocommit(false); $db->close(); syslog(LOG_ERR,"Performed First Close."); $db1 = mysqli_connect(MYSQL_HOST, MYSQL_USER, MYSQL_PASS, MYSQL_DB, MYSQL_PORT); $db1->autocommit(false); $db->close(); syslog(LOG_ERR,"Performed Second Close."); // Now lets do a nested close to break this connection cache. $db = mysqli_connect(MYSQL_HOST, MYSQL_USER, MYSQL_PASS, MYSQL_DB, MYSQL_PORT); $db1 = mysqli_connect(MYSQL_HOST, MYSQL_USER, MYSQL_PASS, MYSQL_DB, MYSQL_PORT); $db1->autocommit(false); $db1->close(); syslog(LOG_ERR,"Performed Third Close."); $db->autocommit(false); $db->close(); syslog(LOG_ERR,"Performed Fourth Close.");

(0001716) dberry 01-11-07 11:27	Here is the modified env.getConnection(). It is a removal of the caching logic: /** * Returns the configured database. */ public Connection getConnection(String driver, String url, String userName, String password) throws Exception { DataSource database = _quercus.getDatabase(); if (database != null) return database.getConnection(); database = _quercus.findDatabase(driver, url); if (userName == null \|\| userName.equals("")) return database.getConnection(); return database.getConnection(userName, password); }

(0001720) nam 01-16-07 10:06	php/1418 ('using closed connection' fixed) Quercus hands out connections based on the (host, username, password) tuple. PHP scripts tend to open a new connection without closing the previous connection. For most cases, PHP scripts use the new connection exclusively and the race condition where multiple open connections to the same database tuple are actively used is a non-issue for real applications.

(0001778) nam 03-20-07 10:41	php/1f19

Relationships