Choosing Memcached Slab Growth Factor for Efficient Memory Use
Learn how to pick the Memcached slab growth factor (-I) to match your object sizes, reduce memory waste, and avoid unnecessary evictions.
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Understanding Memcached Slab Allocation and Why Evictions Can Happen With Free Memory
Learn how Memcached’s slab allocator can cause evictions even when total memory appears free, and how to diagnose and mitigate the issue.
Stopping Memcached Evictions with Slab Allocation Tuning
Stop premature Memcached evictions by tuning slab allocation. Learn how to identify internal fragmentation and align slab classes with your data payloads.
Optimizing Memcached Slab Allocation to Prevent Memory Waste
Learn how to identify and fix slab waste in Memcached by tuning growth factors and analyzing slab distribution to improve cache hit rates.
Memcached item size limits and per-slab-class eviction tradeoffs
Memcached allocates memory through fixed-size slab classes, and each class maintains its own approximate LRU for eviction. The size of a single item is capped—commonly near 1 MiB by default and adjustable through the documented -I startup option—so larger values must either be split across keys or accommodated by raising the limit. The unresolved decision is
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