As the technology industry continues to react to two major CPU bugs, we’re starting to see early signs of performance issues from security patches designed to fix the problems. Epic Games has released a chart of CPU usage after it patched its back-end services to address the Meltdown vulnerability. It shows a roughly 20 percent increase in CPU utilization, immediately after the patches were applied. The company released the chart to “provide a bit more context” around recent login issues and stability with its Fortnite game.

“All of our cloud services are affected by updates required to mitigate the Meltdown vulnerability,” says an Epic Games spokesperson in a forum post. “We heavily rely on cloud services to run our back-end and we may experience further service issues due to ongoing updates.” Epic Games warns that issues may continue next week as the company works with cloud providers to address the issues and prevent further problems arising.

Intel has been rolling out firmware updates to protect against the Meltdown and Spectre CPU vulnerabilities. The flaws affect nearly every device made in the past 20 years, and could allow attackers to use JavaScript code running in a browser to access memory in the attacker’s process. That memory content could contain key strokes, passwords, and other valuable information. Cloud platforms are the most at risk, as multiple customers typically share the same CPU hardware so any security issue could hit multiple businesses at the same time. Cloud providers have been patching fast, and Intel says it has made “significant progress” rolling out updates to protect against Meltdown and Spectre.

Intel has admitted that performance issues will be “highly workload-dependent,” and that further software updates should help. Some Linux admins are reporting performance impacts, and it’s clear we’re only just starting to understand how this could impact internet services.