CloudLinux has support for the following limits:

Limits Units Default Value Description Supported Kernels / OS
SPEED % of a core, or HZ 100% CPU speed limit, relative to a single core, or specified in HZ (portable across CPUs) all
CPU [deprecated] % of  CPU 25% CPU Limit (smallest of CPU & NCPU is used) all
NCPU [deprecated] number of cores 1 CORE Max number of cores (smallest of CPU & NCPU used) all
PMEM KB 1024MB Physical memory limit (RSS field in ps/RES in top). Also includes shared memory and disk cache CL7, CL6, CL5 hybrid kernel, CL5 lve1.x+ kernel
VMEM KB 1024MB Virtual memory limit (VSZ field in ps/VIRT in top) all
IO KB/sec 1024KB/sec IO throughput – combines both read & write operations CL7, CL6 lve1.1.9+ kernel, CL5 hybrid kernel
IOPS [requires lve1.3+] Operations per second 0 Restricts total number of read/write operations per second. CL7, CL6, CL5 hybrid kernels lve1.3+
NPROC number 100 Max number of processes within LVE CL7, CL6, CL5 hybrid kernel, CL5 lve1.x+ kernel
EP number 20 Limit on entry processes. Usually represents max number of concurrent connections to apache dynamic scripts as well as SSH and cron jobs running simultaneously. all

Bellow you can find recommendations for your typical shared hosting setup. The recommendations don?t depend on the power of your server. They only depend on how ?fast? you read more