If I know an index will have unique values, how will it affect performance on inserts or selects if I declare it as such. If the optimiser knows the index is unique how will that affect the query plan? I understand that specifying uniquenes can serve to preserve integrity, but leaving that discussion aside for […]
Category: performance
How can I speed up Perl’s readdir for a directory with 250,000 files?
I am using Perl readdir to get file listing, however, the directory contains more than 250,000 files and this results long time (longer than 4 minutes) to perform readdir and uses over 80MB of RAM. As this was intended to be a recurring job every 5 minutes, this lag time will not be acceptable. More […]