Yi-Wen,

The latency you are experiencing is by-design for a large-ish computing
cluster.  The normal life-cycle for a Job is:

Received WaitingForDriver WaitingForResources
Assigned
Initializing
Running
Completing
Completed

There are some knobs you can turn to tune for your situation.

1. DUCC intra-daemon communications - states affected: All

DUCC is implemented as a small collection of daemons that communicate with
each other at discrete publishing intervals.  The publishing intervals are
configured in $DUCC_HOME/resources/ducc.properties.  The default interval
values are on the order of 15-60 seconds.  At the cost of more chatter
between daemons on the network, you can try lowering some of these values.

These times are the current default ones and are specified in milliseconds:

ducc.jd.state.publish.rate=15000
ducc.orchestrator.state.publish.rate=10000
ducc.pm.state.publish.rate=15000

I have not tried this myself, but perhaps try lowering them to:

ducc.jd.state.publish.rate=2000
ducc.orchestrator.state.publish.rate=1000
ducc.pm.state.publish.rate=1000

2. DUCC scheduling - state affected: WaitingForResources

The DUCC scheduler does not do continuous resource management, but rather
calculates a desired allocation at discrete intervals.  After each
scheduling cycle, the scheduler publishes its layout for the other daemons
to implement.  By default, the scheduler is doing this calculation and
publication whenever it receives an orchestrator.state publication:

ducc.rm.state.publish.ratio = 1

This seems fine as is.

3. DUCC deployment of Job - states affected: WaitingForDriver, Initializing

Once a Job is accepted, the Job Driver [your CollectionReader] and one or
more Job Processes [your AnlaysisEngine] must be launched.

The partial sequence of states here are:

WaitingForDriver: The Job Driver is launched, and not until it reports that
is is ready to produce work items will the next state (WaitingForResources)
occur
...
Initializing: A Job Process is launched, and not until it has completed
initialization of all threads will it ask the Job Driver for the first work
item
Running: The first work item has been dispatched

Minimizing the time for your CR to initialize will help make the transition
from WaitingForDriver to WaitingForResources faster.
Minimizing the time for your AE to initialize will help make the transition
from Initializing to Running faster.

Hope this helps.

Lou.

On Sun, Nov 29, 2015 at 11:25 PM, Yi-Wen Liu <[email protected]> wrote:

> Hi,
>
> Thanks for the reply, and yes, I only have a single work item.
>
> Thanks,
> Yi-Wen
>
> On Sun, Nov 29, 2015 at 7:45 PM, Eddie Epstein <[email protected]>
> wrote:
>
> > Hi,
> >
> > Yes, there are some site.ducc.property entries that will speed up the
> > timing. Will respond with those tomorrow.
> > Are you often running jobs with only a single work item?
> >
> > Eddie
> >
> > On Sat, Nov 28, 2015 at 7:23 PM, Yi-Wen Liu <[email protected]> wrote:
> >
> > > Hi,
> > >
> > > I am using ducc to process text files(cTAKES), and one of my input is
> > quite
> > > short, about 10 lines.
> > > But it takes more than two minutes to process it, as follows:
> > > After submitting,
> > > 00:00-00:08 > no status
> > > 00:09-00:30 > waiting for driver
> > > 00:31-01:00 > waiting for resources
> > > 01:01-02:00 > initializing
> > > 02:01-02:30 > completing
> > > 02:31 > completed
> > >
> > > Is there any way to lower the preprocessing time?(Time to wait for
> > driver,
> > > resources, initializing...)
> > >
> > > I am wondering why it takes so long before completing, and have tried
> > > different parameter values, for example lower initialization time,
> lower
> > > resources needed, but didn't have much improvement.
> > >
> > > Here's parameters I am using now: process_memory_size 2
> > > process_jvm_args -Xmx4g
> > > driver_jvm_args -Xmx4g
> > > process_thread_count 2
> > > process_per_item_time_max 5
> > > process_deployments_max 999
> > > environment AE_INIT_TIME=5 AE_INIT_RANGE=5 INIT_ERROR=0
> > >
> > > Any suggestion is appreciated.
> > >
> > > Thanks,
> > > Yi-Wen
> > >
> >
>

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