Re: [HTCondor-devel] Need for dynamic slots in top-level collector?

[Brian Bockelman <bbockelm@xxxxxxxxxxx>]

> On Mar 10, 2017, at 11:17 AM, Greg Thain <gthain@xxxxxxxxxxx> wrote:
> 
> On 03/10/2017 10:12 AM, Brian Bockelman wrote:
>> Hi,
>> 
>> CMS is just getting nailed by dynamic slot updates to our top-level collector.
>> 
>> Are these actually needed for negotiation?  Are they only being used by the accountant?  Is there any easy way to utilize the information in the parent slot instead?
> 
> When preemption is disabled, the d-slots are only used by the accountant.  And by "nailed", I assume you mean updates?  

Two things are apparent looking at the collector:
1) Update rates to the top-level collector are still too high.
2) Combined with (1), the sheer number of ads + high update rate means that doing a fork of the collector is expensive in terms of RAM.  Less ads in the collector / less turnover of slots would help.
  - Since the top level collector stops responding if it cannot fork more workers, we effectively are forced to have an unbound number of query workers.

> Also, when preemption is disabled, the negotiatior only selects the few attributes needed for accounting from claimed slots.

Let's assume preemption stays disabled - can we select the Child* attributes and get the information we need from the p-slots?

Brian