Out of the box, ldapdns attained an average of 90 queries per second in our environment. Setting two variables increased that amount dramatically. Before launching ldapdns we set
HANDLERS=128 THREADS=2
This had the effect of increasing throughput to just over 1160 queries per second with peaks at 2920 qps, which is very good. An attempt to increase that further by increasing HANDLERS and THREADS failed: ldapdns either froze completely, or it crashed with a segmentation violation. We note that in our environment the program reacted quite differently depending on the value of the LOG variable: set to an empty value had ldapdns keep up a consistent query rate; set to anything else, the rate of queries was quite erratic. In any case, we were not able to have the program complete our test runs. Given more than about 20,000 queries in rapid succession, the program froze.