Grid Resource Allocation - Grid Computing: Infrastructure, Service, and Applications - page 180

sends an Abort message if one of the RMs cannot make the schedule. The
next time, the client uses the TID to poll the results from Acc. Acc will
return a reservation ID if the co-allocation succeeds, or an error message
if it fails. Note that several acceptors may exist simultaneously to provide
redundancy. The acceptor that the client i rst contacts is the leader. When
the leader fails, one of the other acceptors will automatically take over as
leader for that transaction.
The client can send request messages to acceptors to make, modify, or
cancel the reservations. Each Make action request message needs to dei ne
three elements:

1. “Resource” specii es where to make the reservation.

2. “Schedule” specii es when to make the reservation.

3. “Work” specii es what is to be made.

Modify and Cancel actions share the similar structure of request mes-
sage. The Modify action contains the Resource and Ident element, as well
as new Schedule and/or Work elements, depending on the part to be
changed. The Cancel action contains the Resource and Ident element,
which specii es the reservation to be canceled.
In HARC, all messages are written in XML and sent directly over
HTTPS, which is called transport-level security. All HTTPS connections
are initiated by X.509 certii cates, which means that each Acceptor and
each HARC RM must have its own X.509 credential. HARC can work with
local batch schedulers, such as PBSPro, TorqueMaui, TorqueMoab, LSF,
and so on.
There are some other reservation tools developed in industry and aca-
demia, such as the Generic (Grid) Universal Remote (GUR) [31]. However,
GUR does not support workl ow reservations and cannot be used to
reserve multiple types of resources. HARC provides a co-scheduling
framework suitable for any resource and is shown to be well suited to the
scheduling of large scientii c workl ows.

7. 5
This chapter has discussed grid resource allocation in terms of application
needs, allocation processes, and major approaches to efi cient allocation.
Resource allocation needs include high-throughput computing, resource
co-allocation, time-critical needs, and computing synchronization.
The resource allocation process has three stages: resource discovery,
system selection, and job submission. In order to achieve effective resource

Summary