Jul
13
2017
--

Setting Up Percona PAM with Active Directory for External Authentication

Percona PAM

Percona PAMIn this blog post, we’ll look at how to set up Percona PAM with Active Directory for external authentication.

In my previous article on Percona PAM, I demonstrated how to use Samba as a domain, and how easy it is to create domain users and groups via the samba-tool. Then we configured nss-pam-ldapd and nscd to enumerate user and group information via LDAP calls, and authenticate users from this source.

This time around, I will demonstrate two other ways of using Active Directory for external authentication by joining the domain via SSSD or Winbind. System Security Services Daemon (SSSD) allows you to configure access to several authentication hosts such as LDAP, Kerberos, Samba and Active Directory and have your system use this service for all types of lookups. Winbind, on the other hand, pulls data from Samba or Active Directory only. If you’re mulling over using SSSD or Winbind, take a look at this article on what SSSD or Winbind support.

For both methods, we’ll use realmd. That makes it easy to join a domain and enumerate users from it.

My testbed environment consists of two machines:

Samba PDC
OS: CentOS 7
IP Address: 172.16.0.10
Hostname: samba-10.example.com
Domain name: EXAMPLE.COM
DNS: 8.8.8.8(Google DNS), 8.8.4.4(Google DNS), 172.16.0.10(Samba)
Firewall: none

Note: Please follow the steps in the last article for setting up the Samba PDC environment.

Percona Server 5.7 with LDAP authentication via SSS or WinBind
OS: CentOS 7
IP Address: 172.16.0.21
Hostname: ps-ldap-21.example.com
DNS: 172.16.0.10(Samba PDC)

Installing realmd and Its Dependencies

  1. First, we need to make sure that the time is in sync (since this is a requirement for joining domains). Install NTP and make sure that it starts up at boot time:
    [root@ps-ldap-21 ~]# yum -y install ntp
    * * *
    Installed:
    ntp.x86_64 0:4.2.6p5-25.el7.centos.2
    * * *
    [root@ps-ldap-21 ~]# ntpdate 0.centos.pool.ntp.org
    systemctl enable ntpd.service
    systemc 3 Jul 03:48:35 ntpdate[3708]: step time server 202.90.132.242 offset 1.024550 sec
    [root@ps-ldap-21 ~]# systemctl enable ntpd.service
    Created symlink from /etc/systemd/system/multi-user.target.wants/ntpd.service to /usr/lib/systemd/system/ntpd.service.
    [root@ps-ldap-21 ~]# systemctl start ntpd.service
  2. Install realmd and its dependencies for SSSD or Winbind.
    For SSSD:

    yum -y install realmd oddjob oddjob-mkhomedir sssd adcli samba-common-tools

    For Winbind:

    yum -y install realmd oddjob oddjob-mkhomedir samba-winbind-clients samba-winbind samba-common-tools

Joining the Domain via SSSD and Preparing It for Percona PAM

  1. Run realm discover domain for realmd to discover what type of server it’s connecting to and what packages dependencies need to be installed:
    [root@ps-ldap-21 ~]# realm discover example.com
    example.com
    type: kerberos
    realm-name: EXAMPLE.COM
    domain-name: example.com
    configured: no
    server-software: active-directory
    client-software: sssd
    required-package: oddjob
    required-package: oddjob-mkhomedir
    required-package: sssd
    required-package: adcli
    required-package: samba-common-tools

    Our Samba PDC is detected as an Active Directory Controller, and the packages required have been installed previously.

  2. The next step is to join the domain by running realm join domain. If you want to get more information, add the
    --verbose option

    . You could also add the

    -U user

     option if you want to use a different administrator account.

    [root@ps-ldap-21 ~]# realm join example.com --verbose
     * Resolving: _ldap._tcp.example.com
     * Performing LDAP DSE lookup on: 172.16.0.10
     * Successfully discovered: example.com
    Password for Administrator:
     * Required files: /usr/sbin/oddjobd, /usr/libexec/oddjob/mkhomedir, /usr/sbin/sssd, /usr/bin/net
     * LANG=C LOGNAME=root /usr/bin/net -s /var/cache/realmd/realmd-smb-conf.DM6W2Y -U Administrator ads join example.com
    Enter Administrator's password:
    Using short domain name -- EXAMPLE
    Joined 'PS-LDAP-21' to dns domain 'example.com'
     * LANG=C LOGNAME=root /usr/bin/net -s /var/cache/realmd/realmd-smb-conf.DM6W2Y -U Administrator ads keytab create
    Enter Administrator's password:
     * /usr/bin/systemctl enable sssd.service
    Created symlink from /etc/systemd/system/multi-user.target.wants/sssd.service to /usr/lib/systemd/system/sssd.service.
     * /usr/bin/systemctl restart sssd.service
     * /usr/bin/sh -c /usr/sbin/authconfig --update --enablesssd --enablesssdauth --enablemkhomedir --nostart && /usr/bin/systemctl enable oddjobd.service && /usr/bin/systemctl start oddjobd.service
     * Successfully enrolled machine in realm

    As you can see from the command above, the realm command simplifies SSSD configuration and uses existing tools such as net and authconfig to join the domain and use it as an identity provider.

  3. Let’s test if we enumerate existing accounts by using the
    id

     command:

    [root@ps-ldap-21 ~]# id jervin
    id: jervin: no such user
    [root@ps-ldap-21 ~]# id jervin@example.com
    uid=343401115(jervin@example.com) gid=343400513(domain users@example.com) groups=343400513(domain users@example.com),343401103(support@example.com)

    As you can see, the user can be queried if the domain is specified. So if you want to log in as ‘jervin@example.com’, in Percona Server for MySQL you’ll need to create the user as ‘jervin@example.com’ and not ‘jervin’. For example:

    # Creating user 'jervin@example.com'
    CREATE USER 'jervin@example.com'@'%' IDENTIFIED WITH auth_pam;
    # Logging in as 'jervin@example.com'
    mysql -u 'jervin@example.com'

    If you want to omit the domain name when logging in, you’ll need to replace “use_fully_qualified_names = True” to “use_fully_qualified_names = False” in /etc/sssd/sssd.conf, and then restart SSSD. If you do this, then the user can be found without providing the domain:

    [root@ps-ldap-21 ~]# id jervin
    uid=343401115(jervin) gid=343400513(domain users) groups=343400513(domain users),343401103(support)
    [root@ps-ldap-21 ~]# id jervin@example.com
    uid=343401115(jervin) gid=343400513(domain users) groups=343400513(domain users),343401103(support)

    When you create the MySQL user, you don’t need to include the domain anymore:

    # Creating user 'jervin'
    CREATE USER 'jervin'@'%' IDENTIFIED WITH auth_pam;
    # Logging in as 'jervin'
    mysql -u jervin
  4. Optionally, you can specify which users and groups can log in by adding these settings to SSSD:
    Domain access filter
    Under “[domain/example.com]” /etc/sssd/sssd.conf, you can add the following to specify that only users that are members of support and dba are allowed to use SSSD. For example:

    ad_access_filter = (|(memberOf=CN=dba,CN=Users,DC=example,DC=com)(memberOf=CN=support,CN=Users,DC=example,DC=com))

    Simple filters
    You can use

    realm permit

     or

    realm permit -g

     to allow particular users or groups. For example:

    realm permit jervin
    realm permit -g support
    realm permit -g dba

    You can check sssd.conf on how these ACLs are implemented:

    access_provider = simple
    simple_allow_groups = support, dba
    simple_allow_users = jervin
  5. Finally, configure Percona Server for MySQL to authenticate to SSSD by creating /etc/pam.d/mysqld with this content:
    auth required pam_sss.so
    account required pam_sss.so
  6. Done. All you need to do now is to install Percona Server for MySQL, enable the auth_pam and auth_pam_compat plugins, and add PAM users. You can then check for authentication errors at /var/log/secure for troubleshooting. You could also get verbose logs by adding debug_level=[1-9] to [nss], [pam], or [domain] and then restarting SSSD. You can view the logs from /var/log/sssd.

Joining the Domain via Winbind and Preparing it for Percona PAM

  1. The
    realm

     command assumes that SSSD is used. To change the client software, use

    --client-software=winbind

     instead:

    [root@ps-ldap-21 ~]# realm --client-software=winbind discover example.com
    example.com
        type: kerberos
        realm-name: EXAMPLE.COM
        domain-name: example.com
        configured: no  
        server-software: active-directory
        client-software: winbind
        required-package: oddjob-mkhomedir
        required-package: oddjob
        required-package: samba-winbind-clients
        required-package: samba-winbind
        required-package: samba-common-tools
  2. Since the required packages have already been installed, we can now attempt to join this host to the domain:
    [root@ps-ldap-21 ~]# realm --verbose --client-software=winbind join example.com
     * Resolving: _ldap._tcp.example.com
     * Performing LDAP DSE lookup on: 172.16.0.10
     * Successfully discovered: example.com
    Password for Administrator:
     * Required files: /usr/libexec/oddjob/mkhomedir, /usr/sbin/oddjobd, /usr/bin/wbinfo, /usr/sbin/winbindd, /usr/bin/net
     * LANG=C LOGNAME=root /usr/bin/net -s /var/cache/realmd/realmd-smb-conf.9YEO2Y -U Administrator ads join example.com
    Enter Administrator's password:
    Using short domain name -- EXAMPLE
    Joined 'PS-LDAP-21' to dns domain 'example.com'
     * LANG=C LOGNAME=root /usr/bin/net -s /var/cache/realmd/realmd-smb-conf.9YEO2Y -U Administrator ads keytab create
    Enter Administrator's password:
     * /usr/bin/systemctl enable winbind.service
    Created symlink from /etc/systemd/system/multi-user.target.wants/winbind.service to /usr/lib/systemd/system/winbind.service.
     * /usr/bin/systemctl restart winbind.service
     * /usr/bin/sh -c /usr/sbin/authconfig --update --enablewinbind --enablewinbindauth --enablemkhomedir --nostart && /usr/bin/systemctl enable oddjobd.service && /usr/bin/systemctl start oddjobd.service
     * Successfully enrolled machine in realm
  3. Let’s test if we enumerate existing accounts by using the
    id

     command

    [root@ps-ldap-21 ~]# id jervin
    id: jervin: no such user
    [root@ps-ldap-21 ~]# id jervin@example.com
    uid=10000(EXAMPLEjervin) gid=10000(EXAMPLEdomain users) groups=10000(EXAMPLEdomain users),10001(EXAMPLEsupport)

    Unfortunately for Winbind, users identified with their domains cannot login to Percona Server for MySQL. We need to disable this from the Samba config (performed in the next step).

  4. Edit /etc/samba/smb.conf, and change “winbind use default domain = no” to “winbind use default domain = yes”. Restart the Winbind service. For example:
    vi /etc/samba/smb.conf
    #Look for:
    "winbind use default domain = no"
    #Change to:
    "winbind use default domain = yes"
    systemctl restart winbind.service

    Try running

    id

     again:

    [root@ps-ldap-21 ~]# id jervin
    uid=10000(jervin) gid=10000(domain users) groups=10000(domain users),10001(support)
    [root@ps-ldap-21 ~]# id jervin@example.com
    id: jervin@example.com: no such user

    When you create the MySQL user, do not include the domain name. For example:

    # Creating user 'jervin'
    CREATE USER 'jervin'@'%' IDENTIFIED WITH auth_pam;
    # Logging in as 'jervin'
    mysql -u jervin
  5. Finally, configure Percona Server for MySQL to authenticate to Winbind by creating /etc/pam.d/mysqld with this content:
    auth required pam_winbind.so
    account required pam_winbind.so

You can debug authentication attempts by reviewing the logs at /var/log/secure. You may also change “auth required pam_winbind.so” to “auth required pam_winbind.so debug” in /etc/pam.d/mysqld to get verbose logging in the same file.

As for filtering who can authenticate with Winbind, you can add

require_membership_of=group_name

 under the [global] section of /etc/security/pam_winbind.conf

You’ll need to restart winbind daemon to apply the changes.

Conclusion

Thanks to realmd, it’s easier to setup Active Directory as an identity provider. With minimal configuration tweaks, you can use the identity provider to authenticate MySQL users.

Jul
11
2017
--

Thread_Statistics and High Memory Usage

thread_statistics

thread_statisticsIn this blog post, we’ll look at how using thread_statistics can cause high memory usage.

I was recently working on a high memory usage issue for one of our clients, and made some interesting discoveries: high memory usage with no bounds. It was really tricky to diagnose.

Below, I am going to show you how to identify that having thread_statistics enabled causes high memory usage on busy systems with many threads.

Part 1: Issue Background

I had a server with 55.0G of available memory. Percona Server for MySQL version:

Version | 5.6.35-80.0-log Percona Server (GPL), Release 80.0, Revision f113994f31
                 Built On | debian-linux-gnu x86_64

We have calculated approximately how much memory MySQL can use in a worst case scenario for max_connections=250:

mysql> select ((@@key_buffer_size+@@innodb_buffer_pool_size+@@innodb_log_buffer_size+@@innodb_additional_mem_pool_size+@@net_buffer_length+@@query_cache_size)/1024/1024/1024)+((@@sort_buffer_size+@@myisam_sort_buffer_size+@@read_buffer_size+@@join_buffer_size+@@read_rnd_buffer_size+@@thread_stack)/1024/1024/1024*250);
+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| ((@@key_buffer_size+@@innodb_buffer_pool_size+@@innodb_log_buffer_size+@@innodb_additional_mem_pool_size+@@net_buffer_length+@@query_cache_size)/1024/1024/1024)+((@@sort_buffer_size+@@myisam_sort_buffer_size+@@read_buffer_size+@@join_buffer_size+@@read_rnd |
+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| 12.445816040039 |
+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
1 row in set (0.00 sec)

So in our case, this shouldn’t be more than ~12.5G.

After MySQL Server has been restarted, it allocated about 7G. After running for a week, it reached 44G:

# Memory #####################################################
       Total | 55.0G
        Free | 8.2G
        Used | physical = 46.8G, swap allocated = 0.0, swap used = 0.0, virtual = 46.8G
      Shared | 560.0k
     Buffers | 206.5M
      Caches | 1.0G
       Dirty | 7392 kB
     UsedRSS | 45.3G
  Swappiness | 60
 DirtyPolicy | 20, 10
 DirtyStatus | 0, 0

# Top Processes ##############################################
  PID USER      PR  NI    VIRT    RES    SHR S  %CPU %MEM     TIME+ COMMAND
 2074 mysql     20   0 53.091g 0.044t   8952 S 126.0 81.7  34919:49 mysqld

I checked everything that could be related to the high memory usage (for example, operating system settings such as Transparent Huge Pages (THP), etc.). But I still didn’t find the cause (THP was disabled on the server). I asked my teammates if they had any ideas.

Part 2: Team Is on Rescue

After brainstorming and reviewing the status, metrics and profiles again and again, my colleague (Yves Trudeau) pointed out that User Statistics is enabled on the server.

User Statistics adds several INFORMATION_SCHEMA tables, several commands, and the

userstat

 variable. The tables and commands can be used to better understand different server activity, and to identify the different load sources. Check out the documentation for more information.

mysql> show global variables like 'user%';
+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| userstat      | ON    |
+---------------+-------+
mysql> show global variables like 'thread_statistics%';
+-------------------------------+---------------------------+
| Variable_name                 | Value                     |
+-------------------------------+---------------------------+
| thread_statistics             | ON                        |
+-------------------------------+---------------------------+

Since we saw many threads running, it was a good option to verify this as the cause of the issue.

Part 3: Cause Verification – Did It Really Eat Our Memory?

I decided to apply some calculations, and the following test cases to verify the cause:

  1. Looking at the THREAD_STATISTICS table in the INFORMATION_SCHEMA, we can see that for each connection there is a row like the following:
    mysql> select * from THREAD_STATISTICS limit 1G
    *************************** 1. row ***************************
    THREAD_ID: 3566
    TOTAL_CONNECTIONS: 1
    CONCURRENT_CONNECTIONS: 0
    CONNECTED_TIME: 30
    BUSY_TIME: 0
    CPU_TIME: 0
    BYTES_RECEIVED: 495
    BYTES_SENT: 0
    BINLOG_BYTES_WRITTEN: 0
    ROWS_FETCHED: 27
    ROWS_UPDATED: 0
    TABLE_ROWS_READ: 0
    SELECT_COMMANDS: 11
    UPDATE_COMMANDS: 0
    OTHER_COMMANDS: 0
    COMMIT_TRANSACTIONS: 0
    ROLLBACK_TRANSACTIONS: 0
    DENIED_CONNECTIONS: 0
    LOST_CONNECTIONS: 0
    ACCESS_DENIED: 0
    EMPTY_QUERIES: 0
    TOTAL_SSL_CONNECTIONS: 1
    1 row in set (0,00 sec)
  2. We have 22 columns, each of them BIGINT, which gives us ~ 176 bytes per row.
  3. Let’s calculate how many rows we have in this table at this time, and check once again in an hour:
    mysql> select count(*) from information_schema.thread_statistics;
    +----------+
    | count(*) |
    +----------+
    | 7864343  |
    +----------+
    1 row in set (15.35 sec)

    In an hour:

    mysql> select count(*) from information_schema.thread_statistics;
    +----------+
    | count(*) |
    +----------+
    | 12190801 |
    +----------+
    1 row in set (24.46 sec)
  4. Now let’s check on how much memory is currently in use:

    PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
    2096 mysql 20 0 12.164g 0.010t 16036 S 173.4 18.9 2274:51 mysqld
  5. We have 12190801 rows in the THREAD_STATISTICS table, which is ~2G in size.
  6. Issuing the following statement cleans up the statistics:

    mysql> flush thread_statistics;
    mysql> select count(*) from information_schema.thread_statistics;
    +----------+
    | count(*) |
    +----------+
    | 0        |
    +----------+
    1 row in set (00.00 sec)
  7. Now, let’s check again on how much memory is in use:

    ID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 2096 mysql 20 0 12.164g 7.855g 16036 S 99.7 14.3 2286:24 mysqld

As we can see, memory usage drops to the approximate value of 2G that we had calculated earlier!

That was the root cause of the high memory usage in this case.

Conclusion

User Statistics (basically Thread_Statistics) is a great feature that allows us to identify load sources and better understand server activity. At the same time, though, it can be dangerous (from the memory usage point of view) to use as a permanent monitoring solution due to no limitations on memory usage.

As a reminder, thread_statistics is NOT enabled by default when you enable User_Statistics. If you have enabled Thread_Statistics for monitoring purposes, please don’t forget to pay attention to it.

As a next step, we are considering submitting a feature request to implement some default limits that can prevent Out of Memory issues on busy systems.

May
29
2017
--

Percona Monitoring and Management 1.1.4 is Now Available

Percona Monitoring and Management

Percona Monitoring and ManagementPercona announces the release of Percona Monitoring and Management 1.1.4 on May 29, 2017.

For installation instructions, see the Deployment Guide.

This release includes experimental support for MongoDB in Query Analytics, including updated QAN interface.

Query Analytics for MongoDB

To enable MongoDB query analytics, use the mongodb:queries alias when adding the service. As an experimental feature, it also requires the --dev-enable option:

sudo pmm-admin add --dev-enable mongodb:queries

NOTE: Currently, it monitors only collections that are present when you enable MongoDB query analytics. Query data for collections that you add later is not gathered. This is a known issue and it will be fixed in the future.

Query Analytics Redesign

The QAN web interface was updated for better usability and functionality (including the new MongoDB query analytics data). The new UI is experimental and available by specifying /qan2 after the URL of PMM Server.

New Query Analytics web interface

NOTE: The button on the main landing page still points to the old QAN interface.

You can check out the new QAN web UI at https://pmmdemo.percona.com/qan2

New in PMM Server

  • PMM-724: Added the Index Condition Pushdown (ICP) graph to the MySQL InnoDB Metrics dashboard.
  • PMM-734: Fixed the MySQL Active Threads graph in the MySQL Overview dashboard.
  • PMM-807: Fixed the MySQL Connections graph in the MySQL Overview dashboard.
  • PMM-850: Updated the MongoDB RocksDB and MongoDB WiredTiger dashboards.
  • Removed the InnoDB Deadlocks and Index Collection Pushdown graphs from the MariaDB dashboard.
  • Added tooltips with descriptions for graphs in the MySQL Query Response Time dashboard.Similar tooltips will be gradually added to all graphs.

New in PMM Client

  • PMM-801: Improved PMM Client upgrade process to preserve credentials that are used by services.
  • Added options for pmm-admin to enable MongoDB cluster connections.

About Percona Monitoring and Management

Percona Monitoring and Management is an open-source platform for managing and monitoring MySQL and MongoDB performance. Percona developed it in collaboration with experts in the field of managed database services, support and consulting.

PMM is a free and open-source solution that you can run in your own environment for maximum security and reliability. It provides thorough time-based analysis for MySQL and MongoDB servers to ensure that your data works as efficiently as possible.

A live demo of PMM is available at pmmdemo.percona.com.

Please provide your feedback and questions on the PMM forum.

If you would like to report a bug or submit a feature request, use the PMM project in JIRA.

May
26
2017
--

Percona Server for MySQL 5.7.18-15 is Now Available

Percona Server for MySQL 5.7.18-15

Percona Server for MySQL 5.7.18-15Percona announces the GA release of Percona Server for MySQL 5.7.18-15 on May 26, 2017. Download the latest version from the Percona web site or the Percona Software Repositories. You can also run Docker containers from the images in the Docker Hub repository.

Based on MySQL 5.7.18, including all the bug fixes in it, Percona Server for MySQL 5.7.18-15 is the current GA release in the Percona Server for MySQL 5.7 series. Percona’s provides completely open-source and free software. Find release details in the 5.7.18-15 milestone at Launchpad.

Bugs Fixed:
  • The server would crash when querying partitioning table with a single partition. Bug fixed #1657941 (upstream #76418).
  • Running a query on InnoDB table with ngram full-text parser and a LIMIT clause could lead to a server crash. Bug fixed #1679025 (upstream #85835).

The release notes for Percona Server for MySQL 5.7.18-15 are available in the online documentation. Please report any bugs on the launchpad bug tracker.

May
12
2017
--

Percona Server for MySQL 5.7.18-14 is Now Available

Percona Server for MySQL 5.7.18-14

Percona Server for MySQL 5.7.18-14Percona announces the GA release of Percona Server for MySQL 5.7.18-14 on May 12, 2017. Download the latest version from the Percona web site or the Percona Software Repositories. You can also run Docker containers from the images in the Docker Hub repository.

Based on MySQL 5.7.18, including all the bug fixes in it, Percona Server for MySQL 5.7.18-14 is the current GA release in the Percona Server for MySQL 5.7 series. Percona’s provides completely open-source and free software. Find release details in the 5.7.18-14 milestone at Launchpad.

New Features:
Bugs Fixed:
  • Deadlock could occur in I/O-bound workloads when server was using several small buffer pool instances in combination with small redo log files and variable innodb_empty_free_list_algorithm set to backoff algorithm. Bug fixed #1651657.
  • Fixed a memory leak in Percona TokuBackup. Bug fixed #1669005.
  • Compressed columns with dictionaries could not be added to a partitioned table by using ALTER TABLE. Bug fixed #1671492.
  • Fixed a memory leak that happened in case of failure to create a multi-threaded slave worker thread. Bug fixed #1675716.
  • In-place upgrade from Percona Server 5.6 to 5.7 by using standalone packages would fail if /var/lib/mysql wasn’t defined as the datadir. Bug fixed #1687276.
  • Combination of using any audit API-using plugin, like Audit Log Plugin and Response Time Distribution, with multi-byte collation connection and PREPARE statement with a parse error could lead to a server crash. Bug fixed #1688698 (upstream #86209).
  • Fix for a #1433432 bug caused a performance regression due to suboptimal LRU manager thread flushing heuristics. Bug fixed #1631309.
  • Creating Compressed columns with dictionaries in MyISAM tables by specifying partition engines would not result in error. Bug fixed #1631954.
  • It was not possible to configure basedir as a symlink. Bug fixed #1639735.
  • Replication slave did not report Seconds_Behind_Master correctly when running in multi-threaded slave mode. Bug fixed #1654091 (upstream #84415).
  • DROP TEMPORARY TABLE would create a transaction in binary log on a read-only server. Bug fixed #1668602 (upstream #85258).
  • Processing GTIDs in the relay log that were already been executed were causing write/fsync amplification. Bug fixed #1669928 (upstream #85141).
  • Text/BLOB fields were not handling sorting of the empty string consistently between InnoDB and filesort. Bug fixed #1674867 (upstream #81810) by porting a Facebook patch for MySQL.
  • InnoDB adaptive hash index was using a partitioning algorithm which would produce uneven distribution when the server contained many tables with an identical schema. Bug fixed #1679155 (upstream #81814).
  • For plugin variables that are signed numbers, doing a SHOW VARIABLES would always show an unsigned number. Fixed by porting a Facebook patch for MySQL.

Other bugs fixed: #1629250 (upstream #83245), #1660828 (upstream #84786), #1664519 (upstream #84940), #1674299, #1670588 (upstream #84173), #1672389, #1674507, #1675623, #1650294, #1659224, #1662908, #1669002, #1671473, #1673800, #1674284, #1676441, #1676705, #1676847 (upstream #85671), #1677130 (upstream #85678), #1677162, #1677943, #1678692, #1680510 (upstream #85838), #1683993, #1684012, #1684078, #1684264, #1687386, #1687432, #1687600, and #1674281.

The release notes for Percona Server for MySQL 5.7.18-14 are available in the online documentation. Please report any bugs on the launchpad bug tracker.

May
12
2017
--

Percona Server for MySQL 5.6.36-82.0 is Now Available

Percona Server for MySQL 5.7.18-14

Percona Server for MySQL 5.6.36-82.0Percona announces the release of Percona Server for MySQL 5.6.36-82.0 on May 12, 2017. Download the latest version from the Percona web site or the Percona Software Repositories. You can also run Docker containers from the images in the Docker Hub repository.

Based on MySQL 5.6.36, and including all the bug fixes in it, Percona Server for MySQL 5.6.36-82.0 is the current GA release in the Percona Server for MySQL 5.6 series. Percona Server for MySQL is open-source and free – this is the latest release of our enhanced, drop-in replacement for MySQL. Complete details of this release are available in the 5.6.36-82.0 milestone on Launchpad.

New Features:
Bugs Fixed:
  • Deadlock could occur in I/O-bound workloads when server was using several small buffer pool instances in combination with small redo log files and variable innodb_empty_free_list_algorithm set to backoff algorithm. Bug fixed #1651657.
  • Querying TABLE_STATISTICS in combination with a stored function could lead to a server crash. Bug fixed #1659992.
  • tokubackup_slave_info file was created for a master server after taking the backup with Percona TokuBackup. Bug fixed #135.
  • Fixed a memory leak in Percona TokuBackup. Bug fixed #1669005.
  • Compressed columns with dictionaries could not be added to a partitioned table by using ALTER TABLE. Bug fixed #1671492.
  • Fixed a memory leak that happened in case of failure to create a multi-threaded slave worker thread. Bug fixed #1675716.
  • The combination of using any audit API-using plugin, like Audit Log Plugin and Response Time Distribution, with multi-byte collation connection and PREPARE statement with a parse error could lead to a server crash. Bug fixed #1688698 (upstream #86209).
  • Fix for a #1433432 bug in Percona Server 5.6.28-76.1 caused a performance regression due to suboptimal LRU manager thread flushing heuristics. Bug fixed #1631309.
  • Creating Compressed columns with dictionaries in MyISAM tables by specifying partition engines would not result in error. Bug fixed #1631954.
  • It was not possible to configure basedir as a symlink. Bug fixed #1639735.
  • Replication slave did not report Seconds_Behind_Master correctly when running in multi-threaded slave mode. Bug fixed #1654091 (upstream #84415).
  • DROP TEMPORARY TABLE would create a transaction in binary log on a read-only server. Bug fixed #1668602 (upstream #85258).
  • Creating a compression dictionary with innodb_fake_changes enabled could lead to a server crash. Bug fixed #1629257.

Other bugs fixed: #1660828 (upstream #84786), #1664519 (upstream #84940), #1674299, #1683456, #1670588 (upstream #84173), #1672389, #1674507, #1674867, #1675623, #1650294, #1659224, #1660565, #1662908, #1669002, #1671473, #1673800, #1674284, #1676441, #1676705, #1676847 (upstream #85671), #1677130 (upstream #85678), #1677162, #1678692, #1678792, #1680510 (upstream #85838), #1683993, #1684012, #1684078, #1684264, and #1674281.

Release notes for Percona Server for MySQL 5.6.36-82.0 are available in the online documentation. Please report any bugs on the launchpad bug tracker.

May
10
2017
--

Percona Server for MySQL 5.5.55-38.8 is Now Available

Percona Server for MySQL 5.5

Percona Server for MySQL 5.5.55-38.8Percona announces the release of Percona Server for MySQL 5.5.55-38.8 on May 10, 2017. Based on MySQL 5.5.55, including all the bug fixes in it, Percona Server for MySQL 5.5.55-38.8 is now the current stable release in the 5.5 series.

Percona Server for MySQL is open-source and free. You can find release details in the 5.5.55-38.8 milestone on Launchpad. Downloads are available here and from the Percona Software Repositories.

New Features:
  • Percona Server 5.5 packages are now available for Ubuntu 17.04 (Zesty Zapus).
Bugs Fixed:
  • If a bitmap write I/O errors happened in the background log tracking thread while a FLUSH CHANGED_PAGE_BITMAPS is executing concurrently it could cause a server crash. Bug fixed #1651656.
  • Querying TABLE_STATISTICS in combination with a stored function could lead to a server crash. Bug fixed #1659992.
  • Queries from the INNODB_CHANGED_PAGES table would needlessly read potentially incomplete bitmap data past the needed LSN range. Bug fixed #1625466.
  • It was not possible to configure basedir as a symlink. Bug fixed #1639735.

Other bugs fixed: #1688161, #1683456, #1670588 (upstream #84173), #1672389, #1675623, #1660243, #1677156, #1680061, #1680510 (upstream #85838), #1683993, #1684012, #1684025, and #1674281.

Find the release notes for Percona Server for MySQL 5.5.55-38.8 in our online documentation. Report bugs on the launchpad bug tracker.

Apr
27
2017
--

Percona Live 2017: Day Three Keynotes

Percona Live Keynotes

Welcome to the third (and final) day of the Percona Live Open Source Database Conference 2017, and the third (and final) set of Percona Live keynotes! The enthusiasm hasn’t waned here at Percona Live, and we had a full house on Thursday morning!

Day three of the conference kicked off with three keynotes talks, and ended with the Community Awards Ceremony:

Percona Live Keynote AirBnBSpinaltap: Airbnb’s Change Data Capture System

Xinyao Hu (AirBnB)

In this talk, Xinyao introduced Airbnb’s change data change system, Spinaltap. He briefly covered its design, and focused on various use cases inside Airbnb. These use cases covered both online serving production and offline large distributed batch processing.

Percona Live Keynote PerconaHow Percona Contributes to the Open Source Database Ecosystem

Peter Zaitsev (Percona)

Peter Zaitsev, CEO of Percona, discussed the growth and adoption of open source databases, and Percona’s commitment to remaining an unbiased champion of the open source database ecosystem. Percona remains committed to providing open source support and solutions to its customers, users and the community. He also provided updates and highlighted exciting new developments in Percona Server software for MySQL and MongoDB.

Percona Live Keynote BookingMonitoring Booking.com without looking at MySQL

Jean-François Gagné (Booking.com)

Jean-François Gagné presented a fascinating talk about using a metric for observing Booking.com’s system health: bookings per second. It wasn’t a technical deep-dive (not MySQL- or Linux-related) but it is one of the most important metric Booking.com has to detect problems (and customer behavior) on the website. Many things impact this metric, including the time of the day, the day of the week or the season of the year.

Percona Live Keynote Community AwardsCommunity Award Ceremony

Daniel Nichter (Square), Emily Slocombe (SurveyMonkey)

The MySQL Community Awards initiative is an effort to acknowledge and thank individuals and corporations for their contributions to the MySQL ecosystem. It is a from-the-community, by-the-community and for-the-community effort. Awards are given for Community Contributor, Application, and Corporate Contributor. More information can be found here: http://mysqlawards.org.

This year’s winners were:

  • Community: René Cannaò, Simon Mudd, Shlomi Noach
  • Application: Sysbench, Gh-ost
  • Corporate: GitHub, Percona

Congrats to the winners, the entire open source community, and to all the Percona Live attendees this year. There are still sessions today, check them out.

It’s been a great conference, and we’re looking forward to seeing you all at Percona Live Europe!

Apr
21
2017
--

Percona Monitoring and Management 1.1.3 is Now Available

Percona Monitoring and Management

Percona Monitoring and ManagementPercona announces the release of Percona Monitoring and Management 1.1.3 on April 21, 2017.

For installation instructions, see the Deployment Guide.

This release includes several new graphs in dashboards related to InnoDB and MongoDB operation, as well as smaller fixes and improvements.

New in PMM Server

  • PMM-649: Added the InnoDB Page Splits and InnoDB Page Reorgs graphs to the MySQL InnoDB Metrics Advanced dashboard.
  • Added the following graphs to the MongoDB ReplSet dashboard:
    • Oplog Getmore Time
    • Oplog Operations
    • Oplog Processing Time
    • Oplog Buffered Operations
    • Oplog Buffer Capacity
  • Added descriptions for graphs in the following dashboards:
    • MongoDB Overview
    • MongoDB ReplSet
    • PMM Demo

Changes in PMM Client

  • PMM-491: Improved pmm-admin error messages.
  • PMM-523: Added the --verbose option for pmm-admin add.
  • PMM-592: Added the --force option for pmm-admin stop.
  • PMM-702: Added the db.serverStatus().metrics.repl.executor stats to mongodb_exporter. These new stats will be used for graphs in future releases.
  • PMM-731: Added real-time checks to pmm-admin check-network output.
  • The following commands no longer require connection to PMM Server:
    • pmm-admin start --all
    • pmm-admin stop --all
    • pmm-admin restart --all
    • pmm-admin show-passwords

    NOTE: If you want to start, stop, or restart a specific service, connection to PMM Server is still required.

About Percona Monitoring and Management

Percona Monitoring and Management is an open-source platform for managing and monitoring MySQL and MongoDB performance. Percona developed it in collaboration with experts in the field of managed database services, support and consulting.

PMM is a free and open-source solution that you can run in your own environment for maximum security and reliability. It provides thorough time-based analysis for MySQL and MongoDB servers to ensure that your data works as efficiently as possible.

A live demo of PMM is available at pmmdemo.percona.com.

Please provide your feedback and questions on the PMM forum.

If you would like to report a bug or submit a feature request, use the PMM project in JIRA.

Apr
17
2017
--

Experimental Build of MyRocks with Percona Server for MySQL

MyRocks with Percona Server for MySQL

MyRocks with Percona Server for MySQLWe have been working on bringing out a build of MyRocks with Percona Server for MySQL.

MyRocks is a RocksDB-based storage engine. You can find more information about MyRocks here.

While there is still a lot of work to do, I want to share an experimental build of Percona Server for MySQL with MyRocks, which you can use to evaluate and test this engine

(WARNING: in NO WAY is this build supposed to be for production usage! Consider this ALPHA quality.)

The tar.gz binaries are available from our TESTING area. To start Percona Server for MySQL with the MyRocks engine, use following line in my.cnf:

plugin-load=rocksdb=ha_rocksdb.so;rocksdb_cfstats=ha_rocksdb.so;rocksdb_dbstats=ha_rocksdb.so;rocksdb_perf_context=ha_rocksdb.so;rocksdb_perf_context_global=ha_rocksdb.so;rocksdb_cf_options=ha_rocksdb.so;rocksdb_compaction_stats=ha_rocksdb.so;rocksdb_global_info=ha_rocksdb.so;rocksdb_ddl=ha_rocksdb.so;rocksdb_index_file_map=ha_rocksdb.so;rocksdb_locks=ha_rocksdb.so;rocksdb_trx=ha_rocksdb.so

Later we will provide experimental RPM and DEB packages from our testing repositories. Please let us know how MyRocks is working for you!

Powered by WordPress | Theme: Aeros 2.0 by TheBuckmaker.com