Performance & reliability
What is the difference between shared and dedicated vCPU?
Short answer
A shared vCPU is scheduled against other tenants, so under contention your process waits — visible as steal time. A dedicated vCPU is a physical thread reserved for you with nothing else scheduled on it. Shared is fine for idle-most-of-the-time work; dedicated is necessary for anything with a latency requirement.
The price difference is roughly 40–60%, and it buys consistency rather than peak speed. A shared core is just as fast when it runs; it simply does not always run.
Rule of thumb: if a human or a market is waiting for the response, buy dedicated. If a background job is, shared is genuinely fine and cheaper.
See also: vCPU
7 answers in Performance & reliability
- What is CPU steal time and why does it matter? Steal time is the percentage of time your virtual CPU was ready to run but the hypervisor gave the physical core to someone else. It appears as the "s…
- Why is my VPS slow? In order of likelihood: memory exhaustion causing swap thrashing, disk IO saturation, CPU steal time on shared cores, an unoptimised database, or netw…
- How much latency should I expect from a VPS? Within a metro, under 5 ms. Within a continent, 10–40 ms. Across the Atlantic, 70–90 ms. Europe to Asia, 150–200 ms. Antipodal routes, 250–320 ms. Lig…
- How many visitors can a VPS handle? A well-configured 2 vCPU / 4 GB instance serves a static site to millions of monthly visits, a cached WordPress site to roughly 300,000, and an uncach…
- How do I benchmark a VPS? Measure the three things that actually vary: single-thread CPU with sysbench, disk with fio at 4K random read/write, and network with iperf3 to a know…
- How much faster is NVMe than SATA SSD? Roughly five times the random IOPS — about 500,000 versus 90,000 — and around five times lower latency, under 0.1 ms versus about 0.5 ms. Sequential t…