HP Ignite-UX Memory and the buffer cache, Issues Independent of HP-UXrevision, glance, swagent, swagent, swagent, swagent, swagent, swagentd, swagentd, swagentd, swagentd

2.nkthread – There will be a thread created in swagentd for each of the RPC connections that swagentd may need to handle. If you were to increase rpc_max_calls from the default of six to 28, there would be at least 22 more threads active in swagentd.

3.max_thread_proc – As more threads will be active in swagentd, you will need to ensure that max_thread_proc is set at a value that allows all of the additional threads to be created.

Because swagentd is kernel-threaded on HP-UX 11i v2, and there is a lot of work required of swagentd, it is able to utilize more than one CPU on a multi-processor system. With HP-UX 11i v1, swagentd is not able to use more than 100% of one CPU, as it is not kernel-threaded.

Issues Independent of HP-UX revision

When swagent processes are started in order to handle SD-UX requests, they will consume resources such as swap, CPU, and memory. The following issues should be considered when sizing

asystem:

1.The amount of memory SD-UX will consume on the system depends on how many concurrent sessions you have allowed for.

2.The number of concurrent SD-UX sessions will reduce the bandwidth available per system using SD-UX for installation via a network interface.

3.Depending on usage (if multiple swagent processes are attempting to read from disk) the buffer cache may not be large enough to effectively cache SD-UX depots, which would cause performance problems.

Further discussion of these issues follow:

Memory and the buffer cache

The amount of memory consumed by SD-UX depends on your planned concurrent usage. If you are planning for a worst case of 10 concurrent SD-UX-based installs, you should monitor the memory usage of one swagent process during an install. You can use the memory usage of that process to estimate the resources required for the worst case of 10 concurrent install sessions.

If you used glance to track the memory usage of a swagent process, and found that it used a maximum of 16Mb of real memory and 24Mb of virtual memory, you would need to ensure that you had 160Mb of real memory and 240Mb of virtual memory available at peak times to handle the SD-UX sessions86.

For example, the following system would be able to cope with 10 swagent processes running since there is currently 531Mb of free memory:

# swapinfo	-tm	Mb	Mb	PCT	START/	Mb
TYPE	Mb	Mb	Mb	PCT	START/	Mb	PRI	NAME
TYPE	AVAIL	USED	FREE	USED	LIMIT RESERVE		PRI	NAME
dev	1024	0	1024	0%	0	-	1	/dev/vg00/lvol2
dev	3000	0	3000	0%	0	-	0	/dev/vg00/lvol15
reserve	-	211	-211	43%
memory	924	393	531	43%	-	0	-
total	4948	604	4344	12%	-	0	-

86Real and virtual memory usage is likely to be different in your environment. You should see how much memory swagent uses in your environment, and use that value in any memory requirement calculations.

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