The drand48 routine is used to generate random numbers. Also, consider the situation where an application creates the same number of threads as the number of vCPUs. If there are more than 1024 threads and each thread calls the drand48 routine simultaneously, application performance might be reduced.
Workaround: There are two workarounds:
Design multithreaded applications so that only an optimal number of threads call the drand48 routine to avoid lock contention issues.
Use other randomizing routines which do not compete for the same lock or do not take locks at all when generating random numbers.