ywkang
711a9a257f
Metric fixes (test harnesses, deploy artifact + wrong constant):
- wall = max(t_end) - min(t_start): exclude the one-time KV-cache deploy
from the measured decode/prefill step (it was 92-99% of wall, mapping-
invariant, and masked the real per-mapping separation).
- PEAK_PE_HBM_BPS 128 -> 256 B/ns (8 channels/PE x 32 GB/s); the old value
was half the modeled per-PE HBM BW, so hbm_bw_util read >1.0 once wall
was corrected. All six short-context sweep CSVs regenerated/repatched.
Result: the four KV mappings now separate along a {64,32,16,8}-active-PE
ladder (decode 8-kv/1-kv = 4.8x at 8K, 7.4x at 64K), not "modest/tied" as
before; decode is bandwidth-bound at 46-76% of the 256 GB/s per-PE ceiling.
Report (S5.2 rewrite):
- Replace the tied-wall / 8x-per-PE-util claims (both deploy artifacts)
with the corrected separation and a density trade-off (per-CUBE KV
footprint, Fig 16 top panel switched to a wall-invariant metric).
- Add a projected latency-vs-batched-throughput analysis (marked
projected, not measured): dense mappings win throughput, 1-kv wins
latency; converges at long context.
- Regenerate Fig 15/16/17/18; fix plot script hardcoded ROOT path.
Batch experiment (Part 2, cube_base):
- Add backward-compatible cube_base=0 scalar to the decode kernel so a
batched user placed at DPPolicy.cube_start addresses 0-based shards.
Default preserves single-user behavior (32 decode tests pass unchanged).
- New batch harness (skipped): concurrent B>=2 launches hit a sim routing
issue (sip0.cube0.pe8); single-user path verified. Concurrency fix next.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
1.6 KiB
1.6 KiB
| 1 | mode | kv_per_cube | C | S_kv | wall_us | n_pe | gemm_util | math_count | hbm_bw_util | hbm_read_mb | hbm_write_kb | ipcq_kb | kv_cache_per_cube_mb |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2 | A1 | 1 | 8 | 8192 | 34.765078999497696 | 64 | 0.06032352177393696 | 5248 | 0.029685 | 16.0625 | 64.0 | 114688.0 | 2.0 |
| 3 | A1 | 1 | 8 | 16384 | 62.2566439945763 | 64 | 0.06737118692698127 | 10880 | 0.0330246 | 32.0625 | 64.0 | 229376.0 | 4.0 |
| 4 | A1 | 1 | 8 | 32768 | 117.23649402130023 | 64 | 0.07155287327558905 | 22144 | 0.0350062 | 64.0625 | 64.0 | 458752.0 | 8.0 |
| 5 | A1 | 1 | 8 | 65536 | 227.190164006345 | 64 | 0.07384657726472504 | 44672 | 0.0360931 | 128.0625 | 64.0 | 917504.0 | 16.0 |
| 6 | A2 | 2 | 4 | 8192 | 34.98345650027832 | 32 | 0.11989392757596813 | 2624 | 0.0589993 | 16.0625 | 64.0 | 49152.0 | 4.0 |
| 7 | A2 | 2 | 4 | 16384 | 65.32612049105158 | 32 | 0.12841123790818756 | 5440 | 0.0629457 | 32.0625 | 64.0 | 98304.0 | 8.0 |
| 8 | A2 | 2 | 4 | 32768 | 126.01144852332584 | 32 | 0.13314041062637966 | 11072 | 0.0651369 | 64.0625 | 64.0 | 196608.0 | 16.0 |
| 9 | A2 | 2 | 4 | 65536 | 247.3821043861434 | 32 | 0.1356380732680083 | 22336 | 0.0662942 | 128.0625 | 64.0 | 393216.0 | 32.0 |
| 10 | A4 | 4 | 2 | 8192 | 46.571509501108665 | 16 | 0.18012317165281877 | 1312 | 0.0886379 | 16.0625 | 64.0 | 16384.0 | 8.0 |
| 11 | A4 | 4 | 2 | 16384 | 88.98265048367577 | 16 | 0.18854479956273557 | 2720 | 0.0924225 | 32.0625 | 64.0 | 32768.0 | 16.0 |
| 12 | A4 | 4 | 2 | 32768 | 173.195009542468 | 16 | 0.19373786859461295 | 5536 | 0.0947833 | 64.0625 | 64.0 | 65536.0 | 32.0 |
| 13 | A4 | 4 | 2 | 65536 | 341.9424492809754 | 16 | 0.19625777419912674 | 11168 | 0.0959226 | 128.0625 | 64.0 | 131072.0 | 64.0 |
| 14 | B | 8 | 1 | 8192 | 68.50162199999485 | 8 | 0.24491706196386726 | 656 | 0.120523 | 16.0625 | 64.0 | 0.0 | 16.0 |
| 15 | B | 8 | 1 | 16384 | 134.03762199999207 | 8 | 0.25033592434218427 | 1360 | 0.122712 | 32.0625 | 64.0 | 0.0 | 32.0 |
| 16 | B | 8 | 1 | 32768 | 265.1096219999986 | 8 | 0.25313628186615866 | 2768 | 0.123843 | 64.0625 | 64.0 | 0.0 | 64.0 |
| 17 | B | 8 | 1 | 65536 | 527.2536220000293 | 8 | 0.2545600872134325 | 5584 | 0.124418 | 128.0625 | 64.0 | 0.0 | 128.0 |