Dear Galaxy Developers, I administer a Galaxy instance at Cold Spring Harbor Laboratory, which servers around 200 laboratory members. While our initial hardware purchase has scaled well for the last 3 years, we are finding that we can't quite keep up with rising the demand for compute-intensive jobs, such as mapping. We are hesitant to consider buying more hardware to support the load, since we can't expect that solution to scale. Rather, we are attempting to set up Galaxy to queue jobs (especially mappers) out to the lab's HPCC to accommodate the increasing load. While there is a good number of technical challenges involved in this strategy, I am only writing to ask about one: data locality. Normally, all Galaxy datasets are stored directly on the private server hosting our Galaxy instance. The HPCC cannot mount our Galaxy server's storage (ie: for the purpose of running jobs reading/writing datasets) for security reasons. However, we can mount a small portion of the HPCC file system to our Galaxy server. Storage on the HPCC is at a premium, so we can't afford to just let newly created (or copied) datasets just sit there. It follows that we need a mechanism for maintaining temporary storage in the (restricted) HPCC space which allows for transfer of input datasets to the HPCC (so they will be visible to jobs running there) and transfer of output datasets back to persistent storage on our server. I am in the process of analyzing when/where/how exact path names are substituted into tool command lines, looking for potential hooks to facilitate the staging/unstaging of data before/after job execution on the HPCC. I have found a few places where I might try to insert logic for handling this case. Before modifying too much of Galaxy's core code, I would like to know if there is a recommended method for handling this situation and whether other members of the Galaxy community have implemented fixes or workarounds for this or similar data locality issues. If you can offer either type of information, I shall be most grateful. Of course, if the answer were that there were no recommended or known technique, then that would be valuable information too. Thank you in advance, Eric Paniagua