-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 I'm going to start work on VCL-78 which is an addition to the frontend XML RPC API to allow the backend to call the frontend for allocating computers for block reservations. Currently, the block reservations are created in the frontend, but computers are not allocated to fulfill them because the requested time(s) could be at any point in the future. So, around 6 hours before a requested time, the backend picks up that block reservation time slot, allocates computers for it, and then inserts reload reservations early enough for the computers to be preloaded by the start of the time slot.
This results in a fair amount of duplicated code, since the frontend currently handles computer allocation in all other cases. This is how I am planning on implementing it. Please reply with any comments on doing it differently or tweaking it somehow. I'm open to any suggestions. The backend could just call the frontend with the blockTimes id to process, but I'll make it more generic to be more useful in other cases and require that the backend specify several items. function name: XMLRPCblockAllocation parameters: imageid - id of the image to be used start - unix timestamp for the start time (i.e. machines should be prep'd and ready by this time) end - unix timestamp for the end time machinecount - number of computers to allocate usergroupid - id of user group for checking user access to machines ignoreprivileges - 0 (false) or 1 (true) - set to 1 to select computers from any that are mapped to be able to run the image; set to 0 to only select computers from ones that are both mapped and that users in usergroupid have been granted access to through the privilege tree. If this is set to 1, usergroupid is ignored (more on this below). blockTimeid - id from blockTimes table that this will fulfill or 0 if there is not an existing block reservation related to this call returns: the number of machines that were successfully allocated, with 0 indicating a complete failure of not being able to allocate any computers Description of how it will work: The frontend will use the normal scheduling functions to allocate computers and insert them into the blockComputers table. If blockTimeid is 0, new entries will be created in the blockRequest and blockTimes tables. It will create reload reservations for the computers early enough for them to be loaded by the start time based on historical loading times. The ignoreprivileges flag exists to allow more machines to be available for fulfilling block reservations than just those that the user group has access to. The current implementation with the backend doing the processing functions as if ignoreprivileges were set to 1. That's pretty much it. Josh - -- - ------------------------------- Josh Thompson Systems Programmer Virtual Computing Lab (VCL) North Carolina State University [email protected] 919-515-5323 my GPG/PGP key can be found at pgp.mit.edu -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.6 (GNU/Linux) iD8DBQFJigsTV/LQcNdtPQMRAvSuAJkBLrJnfgC+VD/MFVcg6HIM3OIb9QCdGVkL NK5Mjyap5+oeemdm40DEdaQ= =e3CH -----END PGP SIGNATURE-----
