Quick Start - LxRoot Docs

Hard System Resource limits help manage server load within your LxRoot cluster by allocating and limiting server resources to each containerised website. These limits apply to all processes belonging to that website, including PHP workers, forked processes, cron jobs, and SSH sessions.

Critical Performance Note

Websites that exceed their limits will break in undefined ways. If a website is inexplicably slow or experiencing intermittent 500 errors, insufficient assigned system resources is the most likely cause.

Memory Limit

The total system memory the website processes can consume. If reached, the kernel's OOM (Out Of Memory) killer will terminate processes (usually the newest first) to protect the host.

Virtual CPUs

1 vCPU equals 1 core at 100%. Processes exceeding this are throttled (slowed) by the kernel. You can assign partial resources (e.g., 1.5 vCPUs).

Tip: Setting this too low can actually increase memory usage as PHP workers take longer to clear.

IOPS

Disk operations per second. A single PHP request can perform hundreds of IO operations. If reached, processes will hang in D state and continue to consume memory.

IO Bandwidth

The volume of data read/written. Similar to IOPS, reaching this limit causes processes to hang. Be generous here to allow for large file reads.

nproc

Total number of processes. Set this at least +5 higher than your PHP worker limit. Reaching this typically results in HTTP 500 errors.

Hard Disk

The capacity of the website's home directory (App role only). Reaching 100% usage will prevent file writes and may take the site offline.

Setting Limits - Package Level

Limits set at the package level apply to each website hosted on that package.

Open Settings in the left sidebar.
Select Packages.
Scroll to the System resources section.

Legacy Note: Packages created prior to LxRoot 9.0 default to 'Unlimited'. Edit existing packages via Packages > Edit to apply limits.

Setting Limits - Website Overrides

Master Organisations and Resellers can provide specific websites with more (or fewer) resources than their assigned package allows.

Open Websites in the left sidebar.
Select the kebab menu (three dots) on the target website and click Overrides.
Adjust the limits under System resources and click Save.

Inherited

Once overridden, this tag will disappear from the interface for that specific resource.

System Resource Limits