Old: each scheduler process holds a semaphore
while scanning the shared-mem job array.
On machines with many CPUs
there seems to be contention for this semaphore,
causing slow scheduler response and possibly connection failures.
New: Don't hold the semaphore while scanning array.
Instead, if find a job that passes quick_check(),
acquire the semaphore and recheck that the job is present in array
and passes quick_check().
- client: show messages if app_config.xml has unrecognized tags
http://boinc.berkeley.edu/trac/wiki/ClientAppConfig
This lets users do the following:
1) limit the number of concurrent jobs of a given app
(e.g. for WCG apps that are I/O-intensive)
2) Specify the CPU and GPU usage parameters of GPU versions
of a given app.
Implementation notes:
- max app concurrency is enforced in 2 places:
1) when building the initial job run list
2) when enforcing the final job run list
Both are needed to avoid possible starvation.
- however, we don't enforce it during RR simulation.
Doing so could cause erroneous shortfall and work fetch.
This means, however, that work buffering will not work
as expected if you're using max concurrency.