Welcome
Administering
In addition to administering the database server, you can tune performance, replicate data, and archive data.
System administration
These topics contain concepts, procedures, and reference information for database and database server administrators to use for managing and tuning HCL Informix® database servers.
Administrator's Reference
The HCL® Informix® Administrator's Reference includes comprehensive descriptions of HCL Informix configuration parameters, the system-monitoring interface (SMI) tables in the sysmaster database, the syntax of database server utilities such as onmode and onstat, logical-log records, disk structures, event alarms, and unnumbered error messages.
Administrative Utilities
The onstat utility
The onstat utility reads shared-memory structures and provides statistics about the database server at the time that the command runs.
onstat -D command: Print page-read and page-write information
Use the onstat -D command to display page-read and page-write information for the first 50 chunks in each space.

HCL Informix® V15.0.0 documentation
Welcome to the documentation for HCL Informix® 15.0.0 and related client tools and products.
Product overview
HCL Informix® is a fast and scalable database server that manages traditional relational, object-relational, and dimensional databases. Its small footprint and self-managing capabilities are suited to embedded data-management solutions.
Installing
These topics describe how to install HCL Informix® database servers, client products, and modules.
Administering
In addition to administering the database server, you can tune performance, replicate data, and archive data.
- System administration
  These topics contain concepts, procedures, and reference information for database and database server administrators to use for managing and tuning HCL Informix® database servers.
  - List of utilities
    HCL Informix® includes utilities and applications that you can use to perform administrative tasks and capture information about configuration and performance.
  - Administrator's Guide
    The HCL® Informix® Administrator's Guide provides the information required to administer HCL Informix.
  - Administrator's Reference
    The HCL® Informix® Administrator's Reference includes comprehensive descriptions of HCL Informix configuration parameters, the system-monitoring interface (SMI) tables in the sysmaster database, the syntax of database server utilities such as onmode and onstat, logical-log records, disk structures, event alarms, and unnumbered error messages.
    - Configuring and monitoring Informix®
    - Administrative Utilities
      - Overview of Utilities
        The Informix® database server utilities allow you to perform administrative tasks directly from the command line.
      - The finderr utility
        Use the finderr utility to view additional information on Informix® error messages. On UNIX™ and Linux™ platforms, the information appears on the command line. On Windows™ platforms, the information appears in the Error Messages program.
      - The genoncfg Utility
        Use the genoncfg utility to expedite the process of customizing the default Informix® configuration file (onconfig.std) to the host environment and your planned usage of a database server instance.
      - The ifxclone utility
        You use the ifxclone utility to create a server clone from a snapshot of an existing database server.
      - The oncheck Utility
        Use the oncheck utility to check specified disk structures for inconsistencies, repair inconsistent index structures, and display information about disk structures.
      - The onclean utility
        Use the onclean utility to force a shut down of the database server when normal shut down with the onmode utility fails or when you cannot restart the server. The onclean utility attempts to clean up shared memory, semaphores, and stops database server virtual processes.
      - The oncmsm Utility
      - The onconfig_diff utility
        Use the onconfig_diff utility to compare two onconfig files.
      - The ondblog utility
        Use the ondblog utility to change the logging mode for one or more databases.
      - The oninit utility
        The oninit utility starts the database server.
      - The onkstash Utility
        Use the onkstash utility to create a password stash file for an existing PKCS#12 keystore.
      - The onkstore Utility
      - The onlog utility
        The onlog utility displays the contents of a logical-log file, either on disk or on backup.
      - The onmode utility
        Use the onmode utility to change the database server operating mode and perform various other operations on shared memory, sessions, transactions, parameters, and segments.
      - The onparams Utility
        Use the onparams utility to add or drop a logical-log file, change physical-log parameters, and add a new buffer pool.
      - onpassword Syntax
      - The onrestorept Utility
        You can use the onrestorept utility to restore the database server back to the state that it was in just before the start of the failed upgrade.
      - The onspaces utility
        Use the onspaces utility to manage the storage spaces in your database.
      - The onstat utility
        The onstat utility reads shared-memory structures and provides statistics about the database server at the time that the command runs.
        onstat Utility Commands Sorted by Functional Category
        The information in this topic lists onstat commands that are sorted by functional category.
        Monitor the database server status
        To monitor the database server status, view the heading of the onstat command.
        onstat command syntax
        The complete syntax for the onstat command, including information about the interactive mode and how to have options to execute repeatedly.
        onstat command: Equivalent to the onstat -pu command
        If you invoke onstat without any options, the command is interpreted as onstat -pu (the -p option and the -u option).
        onstat - command: Print output header
        All onstat output includes a header. The onstat - command displays only the output header and the value that is returned from this command indicates the database server mode.
        onstat -- command: Print onstat options and functions
        Use the onstat -- command to display a listing of all of the onstat options and their functions. You cannot combine this option with any other flag.
        Running onstat Commands on a Shared Memory Dump File
        You can run onstat commands against a shared memory dump file. The shared memory dump file can be produced explicitly by using the onstat -o command. If the DUMPSHMEM configuration parameter is set to 1 or set to 2, the dump file is created automatically at the time of an assertion failure.
        onstat -a command: Print overall status of the database server
        Use the onstat -a command to display information about the status of the database server. This command does not display information about all of the onstat options, only about those onstat options used for initial troubleshooting.
        onstat -b command: Print buffer information for buffers in use
        Use the onstat -b option to display information about the buffers that are currently in use, including the total number of resident pages in the buffer pool.
        onstat -B command: Prints information about used buffers
        Use the onstat -B option to display information about buffers that are not on the free-list.
        onstat -c command: Print ONCONFIG file contents
        Use the onstat -c command to display the contents of the ONCONFIG file.
        onstat -C command: Print B-tree scanner information
        Use the -C command to display information about the B-tree scanner subsystem and each B-tree scanner thread.
        onstat -d command: Print chunk information
        onstat -D command: Print page-read and page-write information
        Use the onstat -D command to display page-read and page-write information for the first 50 chunks in each space.
        onstat -f command: Print dbspace information affected by dataskip
        Use the -f command to list the dbspaces that the dataskip feature currently affects.
        onstat -F command: Print counts
        Use the onstat -F command to display a count for each type of write that flushes pages to disk.
        onstat -g monitoring options
        The options that you can use with onstat -g command are used for support and debugging only. You can include only one of these options in the onstat -g command.
        onstat -G command: Print TP/XA transaction information
        Use the onstat -G command to display information about global transactions generated through the library.
        onstat -h command: Print buffer header hash chain information
        Use the onstat -h command to display information about the buffer header hash chains (sometimes called "hash buckets") that are used to access pages in each buffer pool.
        onstat -i command: Initiate interactive mode
        Use the onstat -i command to put the onstat utility in the interactive mode.
        onstat -I command: Print general statistics about index operations
        Use the onstat -I command to display instance-wide information about index operations.
        onstat -k command: Print active lock information
        Use the onstat -k command to print information about active locks, including the address of the lock in the lock table.
        onstat -l command: Print physical and logical log information
        Use the onstat -l command to display information about the physical logs, logical logs, and temporary logical logs.
        onstat -L command: Print the number of free locks
        Use the onstat -L command to print the number of free locks on a lock-free list.
        onstat -m command: Print recent system message log information
        Use the onstat -m command to display the 20 most recent lines of the system message log.
        onstat -o command: Output shared memory contents to a file
        Use the onstat -o command to write the contents of shared memory to a specified file for later analysis. If you do not specify an output file, a file named onstat.out is created in the current directory.
        onstat -O command: Print optical subsystem information
        onstat -p command: Print profile counts
        Use the onstat -p command to display information about profile counts either since you started the database server or since you ran the onstat -z command.
        onstat -P command: Print partition information
        Use the onstat -P command to display the partition number and the pages in the buffer pool for all of the partitions.
        onstat -r command: Repeatedly print selected statistics
        Use the onstat -r command to repeatedly print the statistics for other options specified in the command at specified intervals.
        onstat -R command: Print LRU, FLRU, and MLRU queue information
        Use the onstat -R command to display detailed information about the LRU queues, FLRU queues, and MLRU queues. For each queue, the onstat -R command displays the number of buffers in the queue and the number and percentage of buffers that have been modified.
        onstat -s command: Print latch information
        Use the onstat -s command to display general latch information, including the resource that the latch controls.
        onstat -t and onstat -T commands: Print tblspace information
        Use the onstat -t command to display tblspace information for active tblspaces. Use the onstat -T command to display tblspace information for all tblspaces.
        onstat -u command: Print user activity profile
        Use the onstat -u command to display a profile of user activity.
        onstat -x command: Print database server transaction information
        Use the onstat -x command to display transaction information on the database server.
        onstat -X command: Print thread information
        Use the onstat -X command to obtain precise information about the threads that are waiting for buffers.
        onstat -z command: Clear statistics
        Use the onstat -z command to clear database server statistics, including statistics that relate to Enterprise Replication, and set the profile counts to 0.
        Return codes on exiting the onstat utility
        The onstat utility displays a set of return codes when you exit the utility.
    - SQL Administration API
    - Appendixes
  - DB-Access User's Guide
    The HCL® Informix® DB-Access User's Guide describes how to use the utility to access, modify, and retrieve information from HCL Informix database servers.
  - High-Performance Loader User's Guide
    The describes how to use the HCL Informix® to load and unload large quantities of data efficiently to or from Informix databases.
  - Performance Guide
    The HCL® Informix® Performance Guide describes how to configure and operate your HCL Informix database server to improve overall system throughput and to improve the performance of SQL queries.
  - SNMP Subagent Guide
    The describes the Simple Network Management Protocol (SNMP) and the software that you need to use SNMP to monitor and manage HCL Informix® database servers and databases.
  - InformixHQ Guide
    InformixHQ is a modern web console for visualizing, monitoring, and managing your Informix server instances. It is purpose built for ease-of-use, scaling out, and optimizing DevOps needs. It provides critical performance management capabilities, monitoring how key performance metrics are changing over time and tracking how efficiently Informix is running your workload even when you’ve stepped away from your screen. Its monitoring system feeds directly into a customizable alerting system so you can be immediately alerted via email, Twilio, or PagerDuty whenever an issue occurs on one of your Informix database server instances. InformixHQ is designed to be scalable to efficiently manage and monitor as many Informix database server instances as you need. Moreover, it's a tool that can be shared by the DBAs, the app developers, the ops engineers, and management and accessed from any desktop, laptop, or mobile device. InformixHQ is the centralized hub for graphical monitoring, alerting, and administration of your Informix database servers.
- Backup and Restore Guide
  The HCL® Informix® Backup and Restore Guide describes how to use the HCL Informix and ontape utilities to back up and restore database server data. These utilities enable you to recover your databases after data is lost or becomes corrupted due to hardware or software failure or accident.
- Enterprise Replication
  The describes the concepts of data replication using HCL Informix® Enterprise Replication, including how to design your replication system, as well as administer and manage data replication throughout your enterprise.
Migrating and upgrading
You can upgrade to the 15.0.0 release of HCL Informix® or migrate from other database servers to Informix. Upgrading is an in-place migration method that uses your existing hardware and operating system software. Some changes to the Informix database server can affect upgrading from a previous release.
Client APIs and tools
You can use the HCL Informix® implementation of client APIs to develop applications for Informix database servers.
Embedding Informix®
When you embed HCL Informix®, you can use enterprise-class high-availability and high performance with embeddability features such as easy programmability, a small disk and memory footprint, and silent deployment.
Extending Informix®
Beyond standard relational database objects, HCL Informix® can be extended to handle specialized data types, access methods, routines, and other objects. Informix includes many built-in extensions that are fully integrated in the database server. Informix also provides modules, which are packages of extended database objects for a particular purpose and that are installed separately from the database server. Alternatively, you can create your own user-defined objects for Informix.
Data warehousing
In addition to designing and implementing Informix® dimensional databases, you can use tools to create data warehouse applications and optimize your data warehouse queries.
Designing databases
The first step in creating a relational database is to construct a data model, which is a precise, complete definition of the data you want to store. After you prepare your data model, you must implement it as a database and tables. To implement your data model, you first select a data type for each column and then you create a database and tables and populate the tables with data. You can also implement fragmentation strategies and control access to your data.
JSON compatibility
You can use the popular JSON-oriented query language created by MongoDB to interact with data stored in HCL Informix®.
Security
You can secure your Informix® database server and the data that is stored in your Informix databases. You can encrypt data, secure connections, control user privileges and access, and audit data security.
SQL programming
You can use the HCL Informix® implementation of the SQL language to develop applications for Informix database servers.
Troubleshooting HCL Informix®
Several troubleshooting techniques, tools, and resources are available for resolving problems that you encounter in your HCL Informix® database server environment.

onstat -D command: Print page-read and page-write information

Use the onstat -D command to display page-read and page-write information for the first 50 chunks in each space.

Figure 1. Syntax:

Example output

Figure 2. onstat -D command output

Informix Dynamic Server Version 14.10.F -- On-Line -- Up 00:19:16 -- 173060 Kbytes
2023-05-31 12:35:42

Dbspaces
address          number   flags      fchunk   nchunks  pgsize   flags    owner    name
45122028         1        0x20001    1        1        2048     N  BA    informix rootdbs
45255c50         2        0x28001    2        1        2048     N SBA    informix sbspace
45ee2790         3        0x40028001 3        1        2048     N sBA    informix sb_ext1
    External SBLOBspace directories: /work/sbdir1
                                     /work/sbdir2
3 active, 2047 maximum

Chunks
address          chunk/dbs     offset     page Rd  page Wr  pathname
45122280         1      1      0          2273     241      rootdbs_chunk_1
45a42028         2      2      0          29       13       sbspace
46064488         3      3      0          8        22       /work/sb_ext1
3 active, 32766 maximum

Output description

The output of onstat -D is almost identical to the output of onstat -d. The following columns are unique to onstat -D. For information on the other output columns see ids_adr_0504.html#ids_adr_0504.

page Rd: Is the number of pages read
page Wr: Is the number of pages written