For joint K+V compression on RULER-4k, the best splits reverse the PPL/LongBench pattern and are balanced to K-heavy; K_bpd=1 loses roughly 15–30 accuracy points, and KQ-SVD is near zero on Qwen across almost every split.

kBpd: 1 · vBpd: 4 · model: LLaMA-3.1-8B · sides: K+V · method: KV-COBRA_MSE · totalBpd: 5 · contextLength: 4096

kBpd: 2 · vBpd: 3 · model: LLaMA-3.1-8B · sides: K+V · method: KV-COBRA_MSE · totalBpd: 5 · contextLength: 4096

kBpd: 3 · vBpd: 2 · model: LLaMA-3.1-8B · sides: K+V · method: KV-COBRA_MSE · totalBpd: 5 · contextLength: 4096

kBpd: 1 · vBpd: 5 · model: LLaMA-3.1-8B · sides: K+V · method: KV-COBRA_MSE · totalBpd: 6 · contextLength: 4096

kBpd: 2 · vBpd: 4 · model: LLaMA-3.1-8B · sides: K+V · method: KV-COBRA_MSE · totalBpd: 6 · contextLength: 4096

kBpd: 3 · vBpd: 3 · model: LLaMA-3.1-8B · sides: K+V · method: KV-COBRA_MSE · totalBpd: 6 · contextLength: 4096

kBpd: 4 · vBpd: 2 · model: LLaMA-3.1-8B · sides: K+V · method: KV-COBRA_MSE · totalBpd: 6 · contextLength: 4096

kBpd: 1 · vBpd: 6 · model: LLaMA-3.1-8B · sides: K+V · method: KV-COBRA_MSE · totalBpd: 7 · contextLength: 4096

kBpd: 2 · vBpd: 5 · model: LLaMA-3.1-8B · sides: K+V · method: KV-COBRA_MSE · totalBpd: 7 · contextLength: 4096

kBpd: 3 · vBpd: 4 · model: LLaMA-3.1-8B · sides: K+V · method: KV-COBRA_MSE · totalBpd: 7 · contextLength: 4096

kBpd: 4 · vBpd: 3 · model: LLaMA-3.1-8B · sides: K+V · method: KV-COBRA_MSE · totalBpd: 7 · contextLength: 4096

kBpd: 5 · vBpd: 2 · model: LLaMA-3.1-8B · sides: K+V · method: KV-COBRA_MSE · totalBpd: 7 · contextLength: 4096