System Limits | Teradata Vantage - 17.10 - System Limits - Advanced SQL Engine - Teradata Database

Teradata Vantage™ - Database Design

Product
Advanced SQL Engine
Teradata Database
Release Number
17.10
Release Date
July 2021
Content Type
User Guide
Publication ID
B035-1094-171K
Language
English (United States)

The system specifications in the following tables apply to an entire Teradata Vantage configuration.

Miscellaneous System Limits

Parameter Value
Maximum number of combined databases, users, and zones. 4.2 x 109
Maximum number of database objects per system lifetime.

A database object is any object whose definition is recorded in DBC.TVM.

Because the system does not reuse DBC.TVM IDs, this means that a maximum of 1,073,741,824 such objects can be created over the lifetime of any given system. At the rate of creating one new database object per minute, it would take 2,042 years to use 1,073,741,824 unique IDs.

1,073,741,824
Maximum size for a table header. 1 MB
Maximum size of table header cache. 8 x 106 bytes
Maximum size of a response spool row.
  • 1 MB on large-cylinder systems
  • 64 KB on small-cylinder systems
Maximum number of change logs that can be specified for a system at any point in time. 1,000,000
Maximum number of locks that can be placed on aggregate online archive logging tables, databases, or both per request.

The maximum number of locks that can be placed per LOGGING ONLINE ARCHIVE ON request is fixed at 25,000 and cannot be altered.

25,000
Maximum number of 64KB parse tree segments allocated for parsing requests. 12,000
Maximum number of nodes per system configuration.

Limits on vprocs of each type restrict systems with a large number of nodes to fewer vprocs per node.

Systems with the maximum vprocs per node cannot approach the maximum number of nodes.

1,024
Maximum size of a query band. 4,096 UNICODE characters

Message Limits

Parameter Value
Maximum number of CLIv2 parcels per message 256
Maximum request message size (client-to-database) 7 MB

This limit applies to messages to and from client systems and to some internal Vantage messages.

Maximum response message size (database-to-client) 16 MB
Maximum error message text size in a failure parcel 255 bytes

Storage Limits

Parameter Value
Total data capacity ~ 12 TB/AMP
Minimum data block size with small cylinders ~9KB

18 512-byte sectors

Default data block size with small cylinders ~127KB

254 512-byte sectors

Maximum data block size with small cylinders ~256KB

512 512-byte sectors

Minimum data block size with large cylinders ~21KB

42 512-byte sectors

Default data block size with large cylinders ~127KB

254 512-byte sectors

Maximum data block size for a large cylinder system that does not use 4KB alignment 1,023.5KB

2,047 sectors

Maximum data block size for a large cylinder system that uses 4KB alignment 1,024KB

2,048 sectors

Maximum number of data blocks that can be merged per data block merge 8
Maximum merge block ratioblock size for a table. 100% of the maximum multirow block size for a table.

Gateway and Vproc Limits

Parameter Value
Maximum number of sessions per PE. Multiple.

This is true because the gateway runs in its own vproc on each node. See Teradata Vantage™ - Database Utilities, B035-1102 for details.

The exact number depends on whether the gateways belong to different host groups and listen on different IP addresses.

Maximum number of sessions per gateway. Tunable: 1 - 2,147,483,647.

1,200 maximum certified.

The default is 600.

See Teradata Vantage™ - Database Utilities, B035-1102 for details.

  30,720

This includes the sum of all of the following types of vproc for a configuration:

  • AMP

    Access Module Processor vprocs

  • GTW

    Gateway Control vprocs

  • PE

    Parsing Engine vprocs

  • RSG

    Relay Services Gateway vprocs

  • TVS

    Teradata Virtual

Maximum number of AMP vprocs per system. 16,200
Maximum number of GTW vprocs per system.

This is a soft limit that Teradata Services personnel can reconfigure for you.

Each GTW vproc on a node must be in a different host group. If two GTW vprocs are in the same host group, they must be on different nodes.

The default is one GTW vproc per node with all of them assigned to the same host group.
The maximum depends on:
  • Number of IP addresses assigned to each node.
  • Number of host groups configured in the database.

Each gateway on a node must be assigned to a different host group from any other gateway on the same node and each gateway needs to be assigned a disjoint set of IP addresses to service.

This does not mean that all gateways in a system must be assigned to a different host group.

It means that each gateway on the same node must be assigned to a different host group.

Gateways on different nodes can be assigned to the same host group.

Maximum number of PE vprocs per system.

This is a soft limit that Teradata Services personnel can reconfigure for you.

2,048
Maximum number of TVS allocator vprocs per system.

This is a soft limit that Teradata Services personnel can reconfigure for you.

2,048
Maximum number of vprocs, in any combination, per node. 127
Maximum number of AMP vprocs per cluster. 8
Maximum number of external routine protected mode platform tasks per PE or AMP.

This value is derived by subtracting 1 from the maximum total of PE and AMP vprocs per system (because each system must have at least one PE), which is 16,384. This is obviously not a practical configuration.

The valid range is 0 to 20, inclusive. The limit is 20 platform tasks for each platform type, not 20 combined for both. See Teradata Vantage™ - Database Utilities, B035-1102 for details.

20
Maximum number of external routine secure mode platform tasks per PE or AMP.

This value is derived by subtracting 1 from the maximum total of PE and AMP vprocs per system (because each system must have at least one PE), which is 16,384. This is obviously not a practical configuration.

20
Size of a request control block ~ 40 bytes
Default number of lock segments per AMP vproc.

This is controlled by the NumLokSegs parameter in DBS Control.

2
Maximum number of lock segments per AMP vproc.

This is controlled by the NumLokSegs parameter in DBS Control.

8
Default size of a lock segment.

This is controlled by the LockLogSegmentSize parameter in DBS Control.

64 KB
Maximum size of a lock segment.

This is controlled by the LockLogSegmentSize parameter in DBS Control.

1 MB
Default number of locks per AMP 3,200
Maximum number of locks per AMP. 209.000
Maximum size of the lock table per AMP.

The AMP lock table size is fixed at 2 MB and cannot be altered.

2 MB
Maximum size of the queue table FIFO runtime cache per PE.
  • 100 queue table entries
  • 1 MB
Maximum number of SELECT AND CONSUME requests that can be in a delayed state per PE. 24
Amount of private disk swap space required per protected or secure mode server for C/C++ external routines per PE or AMP vproc. 256 KB
Amount of private disk swap space required per protected or secure mode server for Java external routines per node. 30 MB

Hash Bucket Limits

Parameter Value
Number of hash buckets per system.

This value is user-selectable.

The number is user-selectable per system.
The choices are:
  • 65,536
  • 1,048,576

Bucket numbers range from 0 to the system maximum.

Size of a hash bucket The size depends on the number of hash buckets on the system if the system has:
  • 65,536 hash buckets, the size of a hash bucket is 16 bits.
  • 1,048,576 hash buckets, the size of a hash bucket is 20 bits.

Set the default hash bucket size for

your system using the DBS Control utility (see Teradata Vantage™ - Database Utilities, B035-1102 for details).

Interval Histogram Limits

Parameter Value
Number of hash values. 4.2 x 109
Maximum number of intervals per index or column set histogram.

The system-wide maximum number of interval histograms is set using the MaxStatsInterval parameter of the DBS Control record.

500
Default number of intervals per index or column set histogram. 250
Maximum number of equal-height intervals per interval histogram. 500