I think Steven Sagaert makes some good points.
I just did a search forRomio Julia and dammit, got a lot of responses
about a medieval play by some bloke called William Shakespeare.
(ps ROMIO
http://www.mcs.anl.gov/project/romio-high-performance-portable-mpi-io-implementation
)
Well if you want multiple processes to write into the db you should use one
that can handle concurrency, i.e. a "real" DB not a simple desktop/embedded
DB like SQLlite. So for example Postgres or if you do not want to deal with
SQL then use a NOSQL db e.g. mongodb (there are many more). For a
Thanks for the responses.
Raph, thank you again. I very much appreciate your "humble offering".
I'll take a further look into your gist.
Steven, I'm happy to use the right tool for the job...so long as I have an
idea of what it is. Would you care to offer more insights or suggestions
for
that because SQLLite isn't a multi-user DB server but a single user
embedded (desktop) db. Use the right tool for the job.
On Saturday, October 15, 2016 at 7:02:58 PM UTC+2, Ralph Smith wrote:
>
> How are the processes supposed to interact with the database? Without
> extra synchronization
How are the processes supposed to interact with the database? Without
extra synchronization logic, SQLite.jl gives (occasionally)
ERROR: LoadError: On worker 2:
SQLite.SQLiteException("database is locked")
which on the face of it suggests that all workers are using the same
connection, although
It still surprises me how in the scientific computing field people still
refuse to learn about databases and then replicate database functionality
in files in a complicated and probably buggy way. HDF5 is one example,
there are many others. If you want to to fancy search (i.e. speedup search
There are good synchronization primitives for Tasks, and a bit for threads,
but not much for parallel processes. (One could use named system semaphores
on Linux and Windows, but there's no Julia wrapper yet AFAIK.)
I also found management of parallel processes confusing, and good
nontrivial
Thanks for the reply and suggestion, Ralph. I tried to get this working
with semaphores/mutexes/locks/etc. But I've not been having any luck.
Here's a simplified, incomplete version of what I'm trying to do. I'm
hoping that someone can offer a suggestion if they see some sample code.
You can do it with 2 (e.g. integer) channels per worker (requests and
replies) and a task for each pair in the main process. That's so ugly I'd
be tempted to write an
interface to named system semaphores. Or just use a separate file for each
worker.
On Monday, October 10, 2016 at 11:09:39 AM
