File size: 7,375 Bytes
9190eff
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
"""
Long context visualization β€” both models.
"""
import json
import matplotlib.pyplot as plt
import matplotlib.ticker as ticker
import os

def load_long(model_name):
    path = os.path.expanduser(
        f"~/kv-hack/results/{model_name}/long_context_results.json"
    )
    with open(path) as f:
        return json.load(f)

os.makedirs(os.path.expanduser("~/kv-hack/figures"), exist_ok=True)

mistral = load_long("mistral-7b")
llama   = load_long("llama-3-8b")

C_FP16    = "#ef4444"
C_UNIFORM = "#f97316"
C_MISTRAL = "#22c55e"
C_LLAMA   = "#3b82f6"

# ── GRAPH 1: Both Models Side by Side ─────────────────
fig, axes = plt.subplots(1, 2, figsize=(18, 7))

for ax, data, color, title, oom_ctx in [
    (axes[0], mistral, C_MISTRAL, "Mistral-7B", None),
    (axes[1], llama,   C_LLAMA,   "Llama-3-8B", 32768),
]:
    valid = [r for r in data["results"] if "mixed_precision_mb" in r]
    ctx   = [r["context_len"]        for r in valid]
    fp16  = [r["fp16_mb"]            for r in valid]
    uni8  = [r["uniform8_mb"]        for r in valid]
    ours  = [r["mixed_precision_mb"] for r in valid]

    ax.plot(ctx, fp16, 'o-', color=C_FP16,    linewidth=3, markersize=9, label="FP16 Baseline")
    ax.plot(ctx, uni8, 's-', color=C_UNIFORM,  linewidth=3, markersize=9, label="Uniform 8-bit")
    ax.plot(ctx, ours, '^-', color=color,       linewidth=3, markersize=9, label="Per-Head Mixed (Ours)")
    ax.fill_between(ctx, fp16, ours, alpha=0.08, color=color)

    # OOM marker
    if oom_ctx:
        ax.axvline(x=ctx[-1], color=C_FP16, linestyle='--', alpha=0.5)
        ax.text(ctx[-1]*0.92, max(fp16)*0.85,
                "FP16\nOOM β†’", color=C_FP16,
                fontweight='bold', fontsize=10, ha='right')
        # show where ours would be at 32K
        ours_32k = ours[-1] * 2
        ax.annotate(f"Ours at 32K:\n~{ours_32k:.0f}MB βœ…",
                    xy=(ctx[-1], ours[-1]),
                    xytext=(ctx[-2], ours[-1]+200),
                    color=color, fontweight='bold', fontsize=9,
                    arrowprops=dict(arrowstyle='->', color=color))

    # annotate last valid point
    ax.annotate(f"{fp16[-1]/1024:.1f} GB",
                xy=(ctx[-1], fp16[-1]),
                xytext=(-40, 10), textcoords='offset points',
                color=C_FP16, fontweight='bold', fontsize=9)
    ax.annotate(f"{ours[-1]/1024:.1f} GB",
                xy=(ctx[-1], ours[-1]),
                xytext=(-40, -20), textcoords='offset points',
                color=color, fontweight='bold', fontsize=9)

    ax.set_xlabel("Context Length (tokens)", fontsize=12)
    ax.set_ylabel("KV Cache Memory (MB)", fontsize=12)
    ax.set_title(f"{title}\nKV Cache Memory vs Context Length",
                 fontsize=13, fontweight='bold')
    ax.legend(fontsize=10)
    ax.grid(True, alpha=0.3)
    ax.set_xticks(ctx)
    ax.set_xticklabels([f"{c//1024}K" if c >= 1024 else str(c) for c in ctx])

plt.suptitle("Per-Head Mixed-Precision KV Cache β€” Long Context Benchmark\n"
             "Llama-3-8B FP16 OOMs at 32K. Our method fits.",
             fontsize=14, fontweight='bold', y=1.02)
plt.tight_layout()
plt.savefig(os.path.expanduser("~/kv-hack/figures/long_context_both.png"),
            dpi=150, bbox_inches='tight')
print("βœ… Saved figures/long_context_both.png")


# ── GRAPH 2: The OOM Story ────────────────────────────
fig, ax = plt.subplots(figsize=(12, 6))

# project to 32K for both
all_ctx  = [512, 1024, 2048, 4096, 8192, 16384, 32768]
# mistral has all points
m_fp16  = [r["fp16_mb"] for r in mistral["results"] if "fp16_mb" in r]
m_ours  = [r["mixed_precision_mb"] for r in mistral["results"]
           if "mixed_precision_mb" in r]
m_ctx   = [r["context_len"] for r in mistral["results"]
           if "mixed_precision_mb" in r]

# llama valid points
l_valid = [r for r in llama["results"] if "mixed_precision_mb" in r]
l_fp16  = [r["fp16_mb"] for r in l_valid]
l_ours  = [r["mixed_precision_mb"] for r in l_valid]
l_ctx   = [r["context_len"] for r in l_valid]

# A100 40GB memory limit line (minus model weights)
mistral_model_mem = 14.5 * 1024  # MB
llama_model_mem   = 16.0 * 1024  # MB
a100_total        = 40 * 1024    # MB

ax.axhline(y=a100_total - mistral_model_mem,
           color='gray', linestyle='--', alpha=0.7, linewidth=2,
           label=f"A100 headroom (Mistral): {(a100_total-mistral_model_mem)/1024:.0f}GB")
ax.axhline(y=a100_total - llama_model_mem,
           color='gray', linestyle=':', alpha=0.7, linewidth=2,
           label=f"A100 headroom (Llama): {(a100_total-llama_model_mem)/1024:.0f}GB")

ax.plot(m_ctx, m_fp16, 'o-',  color=C_FP16,    linewidth=2.5, markersize=7, label="FP16 (Mistral)")
ax.plot(m_ctx, m_ours, '^-',  color=C_MISTRAL,  linewidth=2.5, markersize=7, label="Ours (Mistral)")
ax.plot(l_ctx, l_fp16, 'o--', color="#f87171",  linewidth=2.5, markersize=7, label="FP16 (Llama)")
ax.plot(l_ctx, l_ours, '^--', color=C_LLAMA,    linewidth=2.5, markersize=7, label="Ours (Llama)")

# OOM annotation
ax.annotate("Llama FP16\nOOM here ❌",
            xy=(16384, l_fp16[-1]),
            xytext=(12000, l_fp16[-1]+400),
            color=C_FP16, fontweight='bold', fontsize=10,
            arrowprops=dict(arrowstyle='->', color=C_FP16))

ax.set_xlabel("Context Length (tokens)", fontsize=13)
ax.set_ylabel("KV Cache Memory (MB)", fontsize=13)
ax.set_title("KV Cache Memory vs GPU Headroom\n"
             "Our method keeps you under the limit longer",
             fontsize=14, fontweight='bold')
ax.legend(fontsize=10, loc='upper left')
ax.grid(True, alpha=0.3)
ax.set_xticks(m_ctx)
ax.set_xticklabels(["512","1K","2K","4K","8K","16K","32K"])
plt.tight_layout()
plt.savefig(os.path.expanduser("~/kv-hack/figures/oom_story.png"),
            dpi=150, bbox_inches='tight')
print("βœ… Saved figures/oom_story.png")


# ── GRAPH 3: Prefill Latency Both Models ─────────────
fig, ax = plt.subplots(figsize=(10, 5))

m_prefill = [r["prefill_ms"] for r in mistral["results"] if "prefill_ms" in r]
l_prefill = [r["prefill_ms"] for r in llama["results"]   if "prefill_ms" in r]

ax.plot(m_ctx, m_prefill, 'o-', color=C_MISTRAL, linewidth=2.5,
        markersize=8, label="Mistral-7B")
ax.plot(l_ctx, l_prefill, 's-', color=C_LLAMA,   linewidth=2.5,
        markersize=8, label="Llama-3-8B")

for x, y in zip(m_ctx, m_prefill):
    ax.annotate(f"{y:.0f}ms", xy=(x, y),
                xytext=(0, 10), textcoords='offset points',
                ha='center', fontsize=8, color=C_MISTRAL)
for x, y in zip(l_ctx, l_prefill):
    ax.annotate(f"{y:.0f}ms", xy=(x, y),
                xytext=(0, -18), textcoords='offset points',
                ha='center', fontsize=8, color=C_LLAMA)

ax.set_xlabel("Context Length (tokens)", fontsize=13)
ax.set_ylabel("Prefill Latency (ms)", fontsize=13)
ax.set_title("Prefill Latency vs Context Length\nBoth Models",
             fontsize=14, fontweight='bold')
ax.legend(fontsize=11)
ax.grid(True, alpha=0.3)
ax.set_xticks(m_ctx)
ax.set_xticklabels(["512","1K","2K","4K","8K","16K","32K"])
plt.tight_layout()
plt.savefig(os.path.expanduser("~/kv-hack/figures/prefill_latency_both.png"),
            dpi=150, bbox_inches='tight')
print("βœ… Saved figures/prefill_latency_both.png")

plt.close('all')
print("\nπŸŽ‰ All long context graphs saved!")