<div dir="ltr">Hi, <div><br><div class="gmail_quote">On Fri, May 22, 2015 at 9:09 AM Erik Søe Sørensen <<a href="mailto:eriksoe@gmail.com">eriksoe@gmail.com</a>> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><p dir="ltr">The "Erlangic" solution would, I think, be to<br>
- have a process which holds the data;<br>
- have one table (sorted_set) which contains {Time, Key}, where Time is some unique monotonously increasing value (now(), or the recently introduced replacement);<br>
- have another table (set) which contains {Key, Time, Value}.<br>
The process owns the tables, and inserts/deletes from both on each update.<br>
In-process data structures could be used instead of tables. <br>
This gives O(log(N)) update time.<br></p></blockquote><div>Indeed I thought about it, but was afraid it would require to increst the limit of the number of ETS tables in my case and I am not sure what does it imply at the moment. The number of queues can be indeed higher than the current limit.<br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><p dir="ltr">
Optimizations can be made, but I'd have to know more about the usage pattern before I'd go into that...</p></blockquote><div><br></div><div>For now I have a process that maintains a queue of items on which I am doing selective receive to fetch from and append to some items to a queue using the queue module. Due to some events an item could have been already handled on another node I need to discard it in the queue.</div><div><br></div><div>Right now to handle that I keep a list of the discarded items apart and when the discarded item is fetched on queue I ignore it and ask for a new item. With the drawback that I have to keep a place of where the items are queued. So i was thinking to have a data structure that would allows me to quickly check a if the item to discard is queued on that node/process and then remove it or mark it as removed (The other way to do it would be filtering the queue  and return the new filtered queue but It would be quite inefficient imo). Not sure what's the best data structure for it if it exists.</div><div><br></div><div>I guess having an ordset + dict (or maps) - or something like it - could also do the trick you define above without requiring an ETS but I not sure if it will perform the same.</div><div><br></div><div>Thanks </div></div></div></div>