Episode 62 of The Linux Podcast dives into Bcache, the Linux kernel block-layer caching that lets you pair a small, fast SSD with a large, slow HDD to create a hybrid volume that performs almost like an all-SSD array. Hosts Lucas and Luna explain how Bcache works at the device-mapper level, how it manages hot and cold data with its writeback and writethrough modes, and why it matters for cost-conscious server builds in mid-2026. They walk through a concrete example: a 256GB NVMe cache fronting a 4TB spinning disk for a media server, cutting average read latency from 12 milliseconds to under 200 microseconds. They also touch on the trade-offs — write amplification, cache coherency, and the risk of losing the cache disk — and how Bcache compares to newer alternatives like LVM cache and dm-cache. If you've ever wondered whether you can get SSD-like speed without buying 4TB of flash, this episode is for you.

#Linux #Bcache #BlockLayerCaching #SSD #HDD #Kernel #DeviceMapper #StoragePerformance #HybridStorage #Writeback #Writethrough #LinuxStorage #ServerOptimization #NVMe #Technology #FexingoBusiness #BusinessPodcast #LinuxPodcast

Keep every episode free: buymeacoffee.com/fexingo