Stop one runaway process from starving everything else on the disk. Use io.latency target-latency control and io.max bandwidth caps to enforce per-workload disk QoS on cgroup v2.
Read MoreKernel CPU Vulnerability Mitigations: Measuring Their Real Performance Cost on VPS Workloads
Spectre, Meltdown, and MDS mitigations cut throughput on some workloads and barely touch others. Measure the actual cost on your instance across syscall-heavy, network, and cryptographic paths.
Read Morezram vs Swap Partition on a VPS: Latency, Memory Savings and When Each One Hurts
On a VPS you cannot add physical RAM, so when memory pressure arrives you have two broad escapes: spill to disk-backed swap, or compress cold pages in RAM with zram….
Read MoreLog Rotation on a VPS: Compression, Retention Windows and Reclaiming Disk Before You Panic
A full disk is the most common avoidable outage on a small VPS, and logs are almost always the culprit. The default logrotate configuration ships with retention tuned for generous…
Read Moresystemd Timer OnCalendar Accuracy: Replay Storms, AccuracySec and RandomizedDelaySec on Small Hosts
How systemd Persistent timers replay missed activations on small VPS hosts, why co-scheduled OnCalendar jobs storm after reboot, and how AccuracySec and RandomizedDelaySec spread the load.
Read MoreTCP BBR vs CUBIC on a VPS WAN Link: What grep bw = (delivery_rate) Actually Tells You
Comparing congestion control algorithms by download speed alone is how you end up with a tuning change that helps one flow shape and hurts another. The kernel exposes a far…
Read Moreext4 Journal Commit Interval on a VPS: The Durability vs Throughput Tradeoff, Measured
Every ext4 filesystem on your VPS makes a silent promise: after fsync() returns, the data is on stable storage. Between those explicit syncs, the kernel batches writes and flushes the…
Read Morevirtio-net Multi-Queue RX/TX Tuning on a VPS: Reducing Single-vCPU Packet Drop
A VPS virtual NIC is not a physical card. It is a paravirtualised device whose packets are delivered by the hypervisor into your guest’s receive path, often through a single…
Read MoreMeasuring Queue Latency vs Device Latency on a Shared-NVMe VPS: A fio + bpftrace Method
When a VPS feels slow, most operators blame CPU first. On a modern hypervisor that is usually wrong: the erratic latency comes from storage, where your writes join a shared…
Read MoreDetecting Configuration Drift on Stateful VPS Hosts: A Hash, sysctl and Unit Manifest Workflow
Configuration drift is any divergence between the state you intended for a host and the state it is actually in. On a stateless worker you can usually ignore it —…
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