Effect of status monitoring on performance
When you configure a server as a hub or spoke server, status monitoring is automatically enabled. Status monitoring requires extra resources on each server on which it is enabled.
Server resource requirements for status monitoring
The resources that are required depend primarily on the number of clients that are managed by the hub and spoke servers.
Also, the hub server requires fewer resources if the spoke servers are running Tivoli® Storage Manager V7.1 or later, or IBM Spectrum Protect™ V7.1.3 or later, than it does if the spoke servers are running V6.3.4 or a later modification of V6.3.
Table 1 summarizes the resource requirements for a server on which status monitoring is enabled.
| Resource requirement | Resource usage for the base level of up to 1000 clients | Resource usage for every 1000 clients over the base level | Example: Resource usage for a spoke server with 2000 clients |
|---|---|---|---|
| Processor usage The value is based on lab measurements that used the Intel X7550 2.00 GHz core. |
1.1 processor cores | 0.1 processor cores | 1.2 processor cores |
| More space in the server database | 2 GB if the server is at V7.1 1 GB if the server is at V7.1.1 or later |
2 GB if the server is at V7.1 1 GB if the server is at V7.1.1 or later |
4 GB if the server is at V7.1 2 GB if the server is at V7.1.1 or later |
| More space for the server archive log The value assumes that a full database backup is completed every 24 hours. |
10 GB | 10 GB | 20 GB |
| Spoke server at V6.3.4 or a later modification of V6.3: Data transfer to the hub server over the network | 30 - 60 MB per hour | 30 - 60 MB per hour | 60 - 120 MB per hour |
| Spoke server at V7.1 or later: Data transfer to the hub server over the network | 5 - 10 MB per hour | 5 - 10 MB per hour | 10 - 20 MB per hour |
Consider adding a buffer of 25% - 50% to the database and log requirements for a server that has a heavy workload. For example:
- A server that is scheduled to back up hundreds of client nodes or virtual-machine file spaces daily
- A server that has many I/O operations per second (IOPS) due to operations such as data deduplication
To verify that disk systems for the server database have the characteristics and configuration that are important for good performance, see Checklist for server database disks.
For information about tools for estimating IOPS capacity for disk systems, see Analyzing the basic performance of disk systems. Also, see the documentation for your operating system.
Extra resource requirements for a hub server
| Resource requirement | For managing spoke servers at V7.1 or later | For managing spoke servers at V6.3.4 or a later modification of V6.3 |
|---|---|---|
| Processor usage The value is based on lab measurements that used the Intel X7550 2.00 GHz core. |
Negligible | More processor resources, equal to 0.1 processor cores for every 1000 clients on all monitored servers (all clients on all spoke servers at V6.3.4 or a later modification of V6.3). |
| More space in the server database | Negligible | If the hub server is at V7.1: More disk space for the database, equal to 2 GB
for every 1000 clients on all monitored spoke servers at V6.3.4 or a later modification of
V6.3. If the hub server is at V7.1.1 or later: More disk space for the database, equal to 1 GB for every 1000 clients across all monitored spoke servers at V6.3.4 or a later modification of V6.3. |
| More space for the server archive log The value assumes that a full database backup is completed every 24 hours. |
More disk space for the archive log, equal to 600 MB for every 1000 clients on all monitored spoke servers at V7.1 or later. | More disk space for the archive log, equal to 10 GB for every 1000 clients on all monitored spoke servers at V6.3.4 or a later modification of V6.3. |
| IOPS capacity for the server database on the hub server | More I/O capability for the database volumes, to support 50 IOPS for every
1000 clients on spoke servers at V7.1 or later. The estimate is based on an average I/O size of 8 KB. |
More I/O capability for the database volumes,
to support 200 IOPS for every 1000 clients on spoke servers at V6.3.4
or a later modification of V6.3. The estimate is based on an average I/O size of 8 KB. |
For a hub server that manages spoke servers, you get optimal performance if the server database is on disks that can process 8 KB operations at the rate of at least 1000 IOPS. To get this IOPS capacity, use a single enterprise-level solid-state drive (SSD). If SSD is not an option, you might want to use a SAN-attached array of 15000-rpm serial-attached SCSI (SAS) hard disk drives, each capable of handling hundreds of 8 KB IOPS. The choice depends on the overall workload of the hub server.
Example of resource requirements for a hub server
Table 3 shows a resource estimate for a hub server with spoke servers that are at V6.3.4 or a later modification of V6.3. Table 4 shows a resource estimate for a hub server with spoke servers that are at V7.1 or later. In both examples, the hub server has 1000 clients, and each of the five spoke servers has 2000 clients.
| Resource requirement | Resource usage for 1000 clients that are managed on the hub server | Resource usage on the hub server for the 10,000 clients that are managed on five spoke servers that are at V6.3.4 or a later modification of V6.3 (2000 clients on each) | Total estimated resource usage |
|---|---|---|---|
| Processor usage The value is based on lab measurements that used the Intel X7550 2.00 GHz core. |
1.1 processor cores | 1 processor core The estimate is based on 0.1 processor core for every 1000 clients on the spoke servers. |
2.1 processor cores |
| More space in the server database | 2 GB if the hub server is at V7.1 1 GB if the hub server is at V7.1.1 or later |
20 GB if the hub server is at V7.1 10 GB if the hub server is at V7.1.1 or later |
22 GB if the hub server is at V7.1 11 GB if the hub server is at V7.1.1 or later |
| More space for the server archive log The value assumes that a full database backup is completed every 24 hours. |
10 GB | 100 GB | 110 GB |
| Spoke server: Data transfer to the hub server over the network | Not applicable | 300 - 600 MB per hour The estimate is based on 30 - 60 MB per hour for every 1000 clients on the spoke servers. |
300 - 600 MB per hour |
| IOPS capacity for the server database on the hub server | 200 IOPS | 2000 IOPS The estimate is based on 200 IOPS for every 1000 clients on the spoke servers. |
2200 IOPS |
| Resource requirement | Resource usage for 1000 clients that are managed on the hub server | Resource usage on the hub server for the 10,000 clients that are managed on five spoke servers at V7.1 or later (2000 clients on each) | Total estimated resource usage |
|---|---|---|---|
| Processor usage The value is based on lab measurements that used the Intel X7550 2.00 GHz core. |
1.1 processor cores | Negligible | 1.1 processor cores |
| More space in the server database | 2 GB if the hub server is at V7.1 1 GB if the hub server is at V7.1.1 or later |
Negligible | 2 GB if the hub server is at V7.1 1 GB if the hub server is at V7.1.1 or later |
| More space for the server archive log The value assumes that a full database backup is completed every 24 hours. |
10 GB | 6 GB The estimate is based on 600 MB for every 1000 clients on the spoke servers. |
16 GB |
| Spoke server: Data transfer to the hub server over the network | Not applicable | 50 - 100 MB per hour The estimate is based on 5 - 10 MB per hour for every 1000 clients on the spoke servers. |
50 - 100 MB per hour |
| IOPS capacity for the server database on the hub server | 200 IOPS | 500 IOPS The estimate is based on 50 IOPS for every 1000 clients on the spoke servers. |
700 IOPS Consider establishing a baseline capacity of 1000 IOPS for the hub server database if the hub server manages any spoke servers. |