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Latest updates, guides, and insights about Valkey monitoring and observability.

When will my Valkey or Redis cache run out of memory? Sizing it with the Cache Size Simulator

used_memory tells you where you are, not where you're going. The Cache Size Simulator samples what your keys actually weigh, projects growth and TTLs forward, tells you when you hit maxmemory and what your eviction policy will do about it, and picks the smallest ElastiCache, MemoryDB, Memorystore or Azure node that still fits in six months. Works on Valkey, Redis OSS and other RESP-compatible databases.

Kristiyan Ivanov•

How Slow DNS Puts Valkey Sentinel Into TILT

A team running BetterDB reported a Valkey Sentinel deployment that kept logging +tilt and flagging +sdown on healthy nodes, with raw IPs and plaintext as the only known workaround. This is the reproduction and the isolation matrix: a blocking getaddrinfo on Sentinel's single-threaded loop is the cause, TLS is not, and an FQDN in announce-ip stalls the peer Sentinels rather than the one that announced it. Verified on Valkey 8.1.8 and 9.0.6.

Kristiyan Ivanov•

OpenTelemetry, both directions: the monitor speaks OTLP in and out

The monitor now speaks OpenTelemetry in both directions: it re-emits its whole Prometheus surface and its events over OTLP, and its /v1/traces endpoint ingests OTLP spans from any instrumented service. That gives BetterDB four positions in your pipeline - feed your collector, be one, produce spans, or consume them and add the one thing a pure trace tool can't: the live database state behind the span. It fits wherever your stack has an OTLP-shaped socket open.

Kristiyan Ivanov•

We benchmarked our semantic cache against Upstash. The thresholds did not transfer.

BetterDB vs @upstash/semantic-cache on four public datasets. Quality is at parity. The same embedding model produced different score distributions on each runtime, so the optimal threshold was different on each side, which is the whole argument for self-tuning. Latency is local Valkey vs a cloud REST API, so we report it as a deployment difference, not a library win. And BetterDB ships OpenTelemetry, Prometheus, and dollars-saved tracking in the MIT library, where Upstash ships none of it.

Kristiyan Ivanov•