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Kernel Tuning (sysctl)

RogueOS includes optimized sysctl parameters for gaming and handheld performance. Click any parameter to see detailed documentation.

Kernel Performance Parameters

What it does

Controls mitigation behavior when the kernel detects a 'split lock' - an atomic instruction spanning multiple cache lines that requires an expensive global bus lock. Starting with Linux 5.19, the kernel penalizes processes that trigger split locks by artificially sleeping for 10ms and serializing access.

Why this value

Setting to 0 disables the performance penalty while retaining kernel log warnings. Several Windows games running under Proton/Wine trigger split locks frequently, including God of War and Street Fighter 6.

Performance impact

Can improve frame rates dramatically in affected games - from unplayable to smooth.

Risks

Increases exposure to denial-of-service attacks from malicious split-lock abuse. Acceptable tradeoff for single-user gaming devices.

Memory/VM Parameters (ZRAM-Optimized)

These parameters are specifically tuned for systems using ZRAM (compressed RAM-based swap), which is the default on RogueOS.

What it does

Controls the kernel's preference between reclaiming memory from the page cache vs. swapping out anonymous pages. Range is 0-200 (extended from 0-100 in Linux 5.8+). At 100, kernel treats swap and page cache reclaim equally. Below 100, prefer dropping page cache. Above 100, prefer swapping.

Why this value

With ZRAM, 'swap' is actually compressed memory - faster than re-reading files from storage. A value of 180 tells the kernel that swapping to ZRAM is significantly cheaper than filesystem I/O, so it should start using ZRAM early, keep file-backed pages in cache, and move inactive anonymous pages to compressed storage.

Performance impact

Better memory utilization on memory-constrained handheld devices. Games can keep more assets in cache while inactive data gets compressed. ZRAM typically achieves 2-3x compression.

Risks

None significant. The high value only makes sense with ZRAM - it would be counterproductive with disk-based swap.