diff --git a/.github/workflows/build-swebench-images.yml b/.github/workflows/build-swebench-images.yml
index 6053db373..c5d0820db 100644
--- a/.github/workflows/build-swebench-images.yml
+++ b/.github/workflows/build-swebench-images.yml
@@ -22,7 +22,12 @@ on:
       max-workers:
         description: 'Number of concurrent builds'
         required: false
-        default: '12'
+        default: '32'
+        type: string
+      build-batch-size:
+        description: 'Number of images to submit per batch'
+        required: false
+        default: '50'
         type: string
       max-retries:
         description: 'Retries per image build'
@@ -54,12 +59,12 @@ on:
 env:
   DATASET: princeton-nlp/SWE-bench_Verified
   SPLIT: test
-  MAX_WORKERS: '12'
+  MAX_WORKERS: '32'
   MAX_RETRIES: '5'
   N_LIMIT: '500'
   INSTANCE_IDS: ''
   SELECT_FILE: ''
-  BUILD_BATCH_SIZE: '15'
+  BUILD_BATCH_SIZE: '50'
   BUILDKIT_PRUNE_KEEP_GB: '60'
   BUILDKIT_PRUNE_THRESHOLD_PCT: '60'
 
@@ -78,7 +83,6 @@ jobs:
 
     runs-on:
       labels: blacksmith-32vcpu-ubuntu-2204
-
     # Allow pushing to GHCR and commenting on issues
     permissions:
       contents: read
@@ -86,6 +90,11 @@ jobs:
       issues: write
 
     steps:
+      - name: Record build start time
+        run: |
+          echo "BUILD_START=$(date +%s)" >> "$GITHUB_ENV"
+          echo "Build started at $(date -u)"
+
       - name: Determine checkout ref
         id: checkout-ref
         run: |
@@ -114,6 +123,7 @@ jobs:
           if [ -n "${{ inputs.dataset }}" ]; then echo "DATASET=${{ inputs.dataset }}" >> "$GITHUB_ENV"; fi
           if [ -n "${{ inputs.split }}" ]; then echo "SPLIT=${{ inputs.split }}" >> "$GITHUB_ENV"; fi
           if [ -n "${{ inputs.max-workers }}" ]; then echo "MAX_WORKERS=${{ inputs.max-workers }}" >> "$GITHUB_ENV"; fi
+          if [ -n "${{ inputs.build-batch-size }}" ]; then echo "BUILD_BATCH_SIZE=${{ inputs.build-batch-size }}" >> "$GITHUB_ENV"; fi
           if [ -n "${{ inputs.max-retries }}" ]; then echo "MAX_RETRIES=${{ inputs.max-retries }}" >> "$GITHUB_ENV"; fi
           # Empty string means "no limit"
           if [ -n "${{ inputs.n-limit }}" ]; then echo "N_LIMIT=${{ inputs.n-limit }}" >> "$GITHUB_ENV"; else echo "N_LIMIT=" >> "$GITHUB_ENV"; fi
@@ -232,6 +242,7 @@ jobs:
             --image ghcr.io/openhands/eval-agent-server \
             --push \
             --max-workers '${MAX_WORKERS}' \
+            --build-batch-size '${BUILD_BATCH_SIZE}' \
             --max-retries '${MAX_RETRIES}'"
 
           # Only include --n-limit if provided (non-empty)
@@ -249,6 +260,21 @@ jobs:
           BUILDKIT_PROGRESS: plain
           BUILDKIT_RESET_ON_FAILURE: 1
 
+      - name: Post-build disk and timing report
+        if: always()
+        run: |
+          set -euo pipefail
+          BUILD_END=$(date +%s)
+          ELAPSED=$(( BUILD_END - ${BUILD_START:-$BUILD_END} ))
+          echo "## Build Timing" >> "$GITHUB_STEP_SUMMARY"
+          echo "**Elapsed:** $((ELAPSED / 60))m $((ELAPSED % 60))s" >> "$GITHUB_STEP_SUMMARY"
+          echo "" >> "$GITHUB_STEP_SUMMARY"
+
+          echo "## Disk Usage After Build" >> "$GITHUB_STEP_SUMMARY"
+          df -h / /var/lib/buildkit 2>/dev/null | tee -a "$GITHUB_STEP_SUMMARY" || true
+          echo "" >> "$GITHUB_STEP_SUMMARY"
+          docker buildx du --verbose 2>/dev/null | head -40 | tee -a "$GITHUB_STEP_SUMMARY" || true
+
       - name: Archive build logs
         if: always()
         run: |
diff --git a/.github/workflows/build-swtbench-images.yml b/.github/workflows/build-swtbench-images.yml
index fe9d07be6..d92b16e0b 100644
--- a/.github/workflows/build-swtbench-images.yml
+++ b/.github/workflows/build-swtbench-images.yml
@@ -22,7 +22,12 @@ on:
       max-workers:
         description: 'Maximum number of parallel workers'
         required: false
-        default: '4'
+        default: '16'
+        type: string
+      agent-build-batch-size:
+        description: 'Number of agent-server images to submit per batch'
+        required: false
+        default: '50'
         type: string
       n-limit:
         description: 'Limit number of images to build (0 for all)'
@@ -72,7 +77,6 @@ jobs:
 
     runs-on:
       labels: blacksmith-32vcpu-ubuntu-2204
-
     permissions:
       contents: read
       packages: write
@@ -82,12 +86,18 @@ jobs:
     env:
       DATASET: eth-sri/SWT-bench_Verified_bm25_27k_zsp
       SPLIT: test
-      MAX_WORKERS: '4'
+      MAX_WORKERS: '16'
+      BUILD_BATCH_SIZE: '50'
       N_LIMIT: '0'
       INSTANCE_IDS: ''
       SELECT_FILE: ''
 
     steps:
+      - name: Record build start time
+        run: |
+          echo "BUILD_START=$(date +%s)" >> "$GITHUB_ENV"
+          echo "Build started at $(date -u)"
+
       - name: Determine checkout ref
         id: checkout-ref
         run: |
@@ -134,6 +144,35 @@ jobs:
         run: |
           make build
 
+      - name: "Preflight: prune cache and verify BuildKit disk"
+        run: |
+          set -euo pipefail
+          KEEP_GB=60
+          echo "Pruning BuildKit cache (target max-storage ${KEEP_GB} GiB, no filters)..."
+          if ! docker buildx prune --all --force --max-storage ${KEEP_GB}g; then
+            docker buildx prune --all --force --keep-storage ${KEEP_GB}g || true
+          fi
+
+          if df -B1 /var/lib/buildkit > /tmp/buildkit_df 2>/dev/null; then
+            LINE=$(tail -n1 /tmp/buildkit_df)
+            TOTAL=$(echo "$LINE" | awk '{print $2}')
+            USED=$(echo "$LINE" | awk '{print $3}')
+            FREE=$(echo "$LINE" | awk '{print $4}')
+            if [ -n "$TOTAL" ] && [ -n "$FREE" ]; then
+              PCT=$(( 100 * USED / TOTAL ))
+              echo "BuildKit disk: used ${USED} / ${TOTAL} bytes (${PCT}%); free ${FREE} bytes"
+              MIN=$((75 * 1024 * 1024 * 1024))
+              if [ "$FREE" -lt "$MIN" ]; then
+                echo "::error::Not enough free space on /var/lib/buildkit (${FREE} bytes free, need >= ${MIN})"
+                exit 1
+              fi
+            else
+              echo "Warning: unable to parse df output for /var/lib/buildkit"
+            fi
+          else
+            echo "Warning: /var/lib/buildkit not found; skipping disk check"
+          fi
+
       - name: Build and push SWT-Bench images
         run: |
           set -euo pipefail
@@ -141,7 +180,8 @@ jobs:
           # Get inputs with defaults
           DATASET="${{ inputs.dataset || 'eth-sri/SWT-bench_Verified_bm25_27k_zsp' }}"
           SPLIT="${{ inputs.split || 'test' }}"
-          MAX_WORKERS="${{ inputs.max-workers || '4' }}"
+          MAX_WORKERS="${{ inputs.max-workers || '16' }}"
+          BUILD_BATCH_SIZE="${{ inputs.agent-build-batch-size || '50' }}"
           N_LIMIT="${{ inputs.n-limit || '0' }}"
           INSTANCE_IDS="${{ inputs.instance-ids }}"
 
@@ -166,6 +206,7 @@ jobs:
             --image ghcr.io/openhands/eval-agent-server \
             --target ${TARGET} \
             --max-workers ${MAX_WORKERS} \
+            --build-batch-size ${BUILD_BATCH_SIZE} \
             --push"
 
           # Add n-limit if specified
@@ -181,6 +222,8 @@ jobs:
         env:
           DOCKER_BUILDKIT: 1
           BUILDKIT_PROGRESS: plain
+          BUILDKIT_RESET_ON_FAILURE: 1
+          OPENHANDS_BUILDKIT_CACHE_MODE: off
 
       - name: Build prebaked eval env images
         if: ${{ inputs.build-eval-env == 'true' }}
@@ -240,6 +283,21 @@ jobs:
           docker ps -a || true
           docker system df || true
 
+      - name: Post-build disk and timing report
+        if: always()
+        run: |
+          set -euo pipefail
+          BUILD_END=$(date +%s)
+          ELAPSED=$(( BUILD_END - ${BUILD_START:-$BUILD_END} ))
+          echo "## Build Timing" >> "$GITHUB_STEP_SUMMARY"
+          echo "**Elapsed:** $((ELAPSED / 60))m $((ELAPSED % 60))s" >> "$GITHUB_STEP_SUMMARY"
+          echo "" >> "$GITHUB_STEP_SUMMARY"
+
+          echo "## Disk Usage After Build" >> "$GITHUB_STEP_SUMMARY"
+          df -h / /var/lib/buildkit 2>/dev/null | tee -a "$GITHUB_STEP_SUMMARY" || true
+          echo "" >> "$GITHUB_STEP_SUMMARY"
+          docker buildx du --verbose 2>/dev/null | head -40 | tee -a "$GITHUB_STEP_SUMMARY" || true
+
       - name: Archive build logs
         if: always()
         run: |
diff --git a/benchmarks/commit0/build_images.py b/benchmarks/commit0/build_images.py
index 3f24567ec..fce111401 100644
--- a/benchmarks/commit0/build_images.py
+++ b/benchmarks/commit0/build_images.py
@@ -124,6 +124,7 @@ def main(argv: list[str]) -> int:
         image=args.image,
         push=args.push,
         max_workers=args.max_workers,
+        build_batch_size=args.build_batch_size,
         dry_run=args.dry_run,
         max_retries=args.max_retries,
         base_image_to_custom_tag_fn=extract_custom_tag,
diff --git a/benchmarks/gaia/build_images.py b/benchmarks/gaia/build_images.py
index 45aee7550..73ca42ad1 100644
--- a/benchmarks/gaia/build_images.py
+++ b/benchmarks/gaia/build_images.py
@@ -94,6 +94,7 @@ def tag_fn(_base: str) -> str:
         image=args.image,
         push=args.push,
         max_workers=1,  # Only building one image
+        build_batch_size=args.build_batch_size,
         dry_run=args.dry_run,
         max_retries=args.max_retries,
         base_image_to_custom_tag_fn=tag_fn,
diff --git a/benchmarks/multiswebench/build_images.py b/benchmarks/multiswebench/build_images.py
index 6c3ef3b9f..c967e8506 100644
--- a/benchmarks/multiswebench/build_images.py
+++ b/benchmarks/multiswebench/build_images.py
@@ -118,6 +118,7 @@ def main():
         ),
         base_image_to_custom_tag_fn=extract_custom_tag,
         max_workers=args.num_workers,
+        build_batch_size=args.build_batch_size,
         dry_run=False,
     )
 
diff --git a/benchmarks/swebench/build_images.py b/benchmarks/swebench/build_images.py
index 5ace5419b..1e7cb8ff8 100644
--- a/benchmarks/swebench/build_images.py
+++ b/benchmarks/swebench/build_images.py
@@ -9,6 +9,9 @@
     --image ghcr.io/openhands/eval-agent-server --target source-minimal
 """
 
+# Use stdlib logging instead of openhands.sdk.get_logger to avoid initializing
+# Rich console state before ProcessPoolExecutor forks (causes deadlocks).
+import logging
 import sys
 from pathlib import Path
 
@@ -23,10 +26,9 @@
 )
 from benchmarks.utils.dataset import get_dataset
 from benchmarks.utils.image_utils import remote_image_exists
-from openhands.sdk import get_logger
 
 
-logger = get_logger(__name__)
+logger = logging.getLogger(__name__)
 WRAPPER_DOCKERFILE = Path(__file__).with_name("Dockerfile.swebench-deps")
 
 
@@ -177,6 +179,7 @@ def main(argv: list[str]) -> int:
         image=args.image,
         push=args.push,
         max_workers=args.max_workers,
+        build_batch_size=args.build_batch_size,
         dry_run=args.dry_run,
         max_retries=args.max_retries,
         base_image_to_custom_tag_fn=extract_custom_tag,
diff --git a/benchmarks/swebenchmultimodal/build_images.py b/benchmarks/swebenchmultimodal/build_images.py
index 987cf7bda..32628bd78 100644
--- a/benchmarks/swebenchmultimodal/build_images.py
+++ b/benchmarks/swebenchmultimodal/build_images.py
@@ -83,6 +83,7 @@ def main(argv: list[str]) -> int:
         image=args.image,
         push=args.push,
         max_workers=args.max_workers,
+        build_batch_size=args.build_batch_size,
         dry_run=args.dry_run,
         max_retries=args.max_retries,
         base_image_to_custom_tag_fn=extract_custom_tag,
diff --git a/benchmarks/swegym/build_images.py b/benchmarks/swegym/build_images.py
index 6c116a020..009bb0dab 100644
--- a/benchmarks/swegym/build_images.py
+++ b/benchmarks/swegym/build_images.py
@@ -87,6 +87,7 @@ def main(argv: list[str]) -> int:
         image=args.image,
         push=args.push,
         max_workers=args.max_workers,
+        build_batch_size=args.build_batch_size,
         dry_run=args.dry_run,
         max_retries=args.max_retries,
         base_image_to_custom_tag_fn=extract_custom_tag,
diff --git a/benchmarks/swesmith/build_images.py b/benchmarks/swesmith/build_images.py
index 51fda90ae..7a1ee7469 100644
--- a/benchmarks/swesmith/build_images.py
+++ b/benchmarks/swesmith/build_images.py
@@ -84,6 +84,7 @@ def main(argv: list[str]) -> int:
         image=args.image,
         push=args.push,
         max_workers=args.max_workers,
+        build_batch_size=args.build_batch_size,
         dry_run=args.dry_run,
         max_retries=args.max_retries,
         base_image_to_custom_tag_fn=extract_custom_tag,
diff --git a/benchmarks/swtbench/build_eval_env_images.py b/benchmarks/swtbench/build_eval_env_images.py
index 2f0ea9862..c64df2883 100644
--- a/benchmarks/swtbench/build_eval_env_images.py
+++ b/benchmarks/swtbench/build_eval_env_images.py
@@ -1,7 +1,10 @@
 from __future__ import annotations
 
+# Use stdlib logging instead of openhands.sdk.get_logger to avoid initializing
+# Rich console state before ProcessPoolExecutor forks (causes deadlocks).
 import argparse
 import json
+import logging
 import os
 import sys
 from pathlib import Path
@@ -13,10 +16,9 @@
 from benchmarks.swtbench.image_utils import ensure_swt_bench_repo
 from benchmarks.utils.dataset import get_dataset
 from benchmarks.utils.image_utils import remote_image_exists
-from openhands.sdk import get_logger
 
 
-logger = get_logger(__name__)
+logger = logging.getLogger(__name__)
 
 
 def select_instance_ids(
diff --git a/benchmarks/swtbench/build_images.py b/benchmarks/swtbench/build_images.py
index 3fcd2d8de..621a3385b 100644
--- a/benchmarks/swtbench/build_images.py
+++ b/benchmarks/swtbench/build_images.py
@@ -44,6 +44,7 @@ def main(argv: list[str]) -> int:
         image=args.image,
         push=args.push,
         max_workers=args.max_workers,
+        build_batch_size=args.build_batch_size,
         dry_run=args.dry_run,
         max_retries=args.max_retries,
         base_image_to_custom_tag_fn=extract_custom_tag,
diff --git a/benchmarks/swtbench/image_utils.py b/benchmarks/swtbench/image_utils.py
index 0aa3ec6f5..387a94085 100644
--- a/benchmarks/swtbench/image_utils.py
+++ b/benchmarks/swtbench/image_utils.py
@@ -1,5 +1,7 @@
 from __future__ import annotations
 
+# Use stdlib logging instead of openhands.sdk.get_logger to avoid initializing
+# Rich console state before ProcessPoolExecutor forks (causes deadlocks).
 import json
 import logging
 import os
@@ -9,10 +11,9 @@
 from typing import Iterable
 
 from benchmarks.swtbench.config import EVAL_DEFAULTS
-from openhands.sdk import get_logger
 
 
-logger = get_logger(__name__)
+logger = logging.getLogger(__name__)
 
 
 def ensure_swt_bench_repo(cache_dir: Path | None = None) -> Path:
diff --git a/benchmarks/utils/build_utils.py b/benchmarks/utils/build_utils.py
index b4e56b9ad..d21c6ed89 100644
--- a/benchmarks/utils/build_utils.py
+++ b/benchmarks/utils/build_utils.py
@@ -3,12 +3,17 @@
 Shared utilities for batch building agent-server images.
 """
 
+# Use stdlib logging instead of openhands.sdk.get_logger to avoid initializing
+# Rich console state before ProcessPoolExecutor forks (causes deadlocks).
 import argparse
 import contextlib
 import io
+import logging
 import os
+import shutil
 import subprocess
 import sys
+import tempfile
 import time
 import tomllib
 from concurrent.futures import ProcessPoolExecutor, as_completed
@@ -29,10 +34,9 @@
 )
 from benchmarks.utils.constants import EVAL_AGENT_SERVER_IMAGE
 from benchmarks.utils.image_utils import local_image_exists, remote_image_exists
-from openhands.sdk import get_logger
 
 
-logger = get_logger(__name__)
+logger = logging.getLogger(__name__)
 
 
 class BuildOutput(BaseModel):
@@ -198,6 +202,57 @@ def _get_sdk_submodule_info() -> tuple[str, str, str]:
     return git_ref, git_sha, sdk_version
 
 
+def _sdk_root() -> Path:
+    benchmarks_root = Path(__file__).resolve().parent.parent.parent
+    return benchmarks_root / "vendor" / "software-agent-sdk"
+
+
+def _pre_build_sdist() -> Path:
+    """
+    Build the SDK sdist once and reuse it across all image builds in a batch.
+
+    The caller must clean up the parent directory of the returned tarball.
+    """
+    sdk_path = _sdk_root()
+    sdist_dir = Path(tempfile.mkdtemp(prefix="shared-sdist-")).resolve()
+
+    logger.info("Pre-building SDK sdist from %s", sdk_path)
+    start = time.time()
+    proc = subprocess.run(
+        ["uv", "build", "--sdist", "--out-dir", str(sdist_dir)],
+        cwd=str(sdk_path),
+        capture_output=True,
+        text=True,
+    )
+    if proc.returncode != 0:
+        shutil.rmtree(sdist_dir, ignore_errors=True)
+        raise RuntimeError(f"Failed to build SDK sdist: {proc.stderr}")
+
+    sdists = sorted(sdist_dir.glob("*.tar.gz"))
+    if len(sdists) != 1:
+        shutil.rmtree(sdist_dir, ignore_errors=True)
+        raise RuntimeError(f"Expected 1 SDK sdist, got {len(sdists)}")
+
+    logger.info("Pre-built SDK sdist in %.1fs: %s", time.time() - start, sdists[0])
+    return sdists[0]
+
+
+@contextlib.contextmanager
+def _prepare_cached_sdist():
+    cached_sdist_path: Path | None = None
+    try:
+        try:
+            cached_sdist_path = _pre_build_sdist()
+        except Exception as e:
+            logger.warning(
+                "Failed to pre-build SDK sdist; each image will build its own: %s", e
+            )
+        yield cached_sdist_path
+    finally:
+        if cached_sdist_path:
+            shutil.rmtree(cached_sdist_path.parent, ignore_errors=True)
+
+
 @contextlib.contextmanager
 def capture_output(base_name: str, out_dir: Path):
     """
@@ -269,6 +324,15 @@ def get_build_parser() -> argparse.ArgumentParser:
     parser.add_argument(
         "--max-workers", type=int, default=1, help="Concurrent builds (be cautious)"
     )
+    parser.add_argument(
+        "--build-batch-size",
+        type=int,
+        default=None,
+        help=(
+            "Number of images to submit per batch. Defaults to BUILD_BATCH_SIZE "
+            "when unset."
+        ),
+    )
     parser.add_argument(
         "--dry-run", action="store_true", help="List base images only, don’t build"
     )
@@ -281,10 +345,14 @@ def build_image(
     custom_tag: str,
     target: TargetType = "source-minimal",
     push: bool = False,
+    cached_sdist: Path | None = None,
 ) -> BuildOutput:
     # Importing here because openhands.agent_server.docker.build runs git checks
     # which fails when installed as a package outside the git repo
-    from openhands.agent_server.docker.build import BuildOptions, build
+    from openhands.agent_server.docker import build as sdk_build_module
+
+    BuildOptions = sdk_build_module.BuildOptions
+    build = sdk_build_module.build
 
     # Get SDK info from submodule to ensure tags use the correct SDK SHA
     git_ref, git_sha, sdk_version = _get_sdk_submodule_info()
@@ -301,13 +369,16 @@ def build_image(
         git_ref=git_ref,
         git_sha=git_sha,
         sdk_version=sdk_version,
+        prebuilt_sdist=cached_sdist,
     )
     for t in opts.all_tags:
         # Check if image exists or not
         if remote_image_exists(t):
             logger.info("Image %s already exists. Skipping build.", t)
             return BuildOutput(base_image=base_image, tags=[t], error=None)
+
     tags = build(opts)
+
     return BuildOutput(base_image=base_image, tags=tags, error=None)
 
 
@@ -358,6 +429,7 @@ def _build_with_logging(
     push: bool = False,
     max_retries: int = 3,
     post_build_fn: Callable[[BuildOutput, bool], BuildOutput] | None = None,
+    cached_sdist: Path | None = None,
 ) -> BuildOutput:
     """
     Module-level function for building a single image with output capture.
@@ -379,7 +451,14 @@ def _build_with_logging(
                 )
                 time.sleep(2 + attempt * 2)
             try:
-                result = build_image(base_image, target_image, custom_tag, target, push)
+                result = build_image(
+                    base_image,
+                    target_image,
+                    custom_tag,
+                    target,
+                    push,
+                    cached_sdist,
+                )
             except Exception as e:
                 result = BuildOutput(
                     base_image=base_image,
@@ -417,6 +496,51 @@ def _build_with_logging(
     raise RuntimeError("Unreachable code reached in _build_with_logging")
 
 
+def _iter_batch_results(
+    batch: list[str],
+    log_dir: Path,
+    image: str,
+    target: TargetType,
+    push: bool,
+    base_image_to_custom_tag_fn: Callable[[str], str] | None,
+    max_workers: int,
+    max_retries: int,
+    post_build_fn: Callable[[BuildOutput, bool], BuildOutput] | None,
+    cached_sdist: Path | None,
+):
+    with ProcessPoolExecutor(max_workers=max_workers) as ex:
+        futures = {}
+        for base in batch:
+            resolved_tag = (
+                base_image_to_custom_tag_fn(base) if base_image_to_custom_tag_fn else ""
+            )
+            fut = ex.submit(
+                _build_with_logging,
+                log_dir=log_dir,
+                base_image=base,
+                target_image=image,
+                custom_tag=resolved_tag,
+                target=target,
+                push=push,
+                max_retries=max_retries,
+                post_build_fn=post_build_fn,
+                cached_sdist=cached_sdist,
+            )
+            futures[fut] = base
+
+        for fut in as_completed(futures):
+            base = futures[fut]
+            try:
+                yield fut.result()
+            except Exception as e:
+                logger.error("Build failed for %s: %r", base, e)
+                yield BuildOutput(
+                    base_image=base,
+                    tags=[],
+                    error=repr(e),
+                )
+
+
 def _update_pbar(
     pbar: tqdm,
     successes: int,
@@ -453,6 +577,7 @@ def build_all_images(
     push: bool = False,
     base_image_to_custom_tag_fn: Callable[[str], str] | None = None,
     max_workers: int = 1,
+    build_batch_size: int | None = None,
     dry_run: bool = False,
     max_retries: int = 3,
     post_build_fn: Callable[[BuildOutput, bool], BuildOutput] | None = None,
@@ -470,6 +595,8 @@ def build_all_images(
         base_image_to_custom_tag_fn: Function to extract a custom tag from a base image.
             Evaluated before scheduling builds so it can safely be a closure.
         max_workers: Number of concurrent builds.
+        build_batch_size: Number of images to submit per batch. If None, use the
+            BUILD_BATCH_SIZE environment variable.
         dry_run: If True, only list base images without building.
         max_retries: Number of times to retry each failed build (default: 3).
         post_build_fn: Optional callback called after each successful build.
@@ -494,7 +621,11 @@ def build_all_images(
 
     # Batch/prune settings (tunable via env to control disk usage on sticky runners)
     # Default to smaller batches and more aggressive pruning on shared runners.
-    batch_size = int(os.getenv("BUILD_BATCH_SIZE", "15"))
+    batch_size = (
+        build_batch_size
+        if build_batch_size is not None
+        else int(os.getenv("BUILD_BATCH_SIZE", "15"))
+    )
     prune_keep_storage_gb = int(os.getenv("BUILDKIT_PRUNE_KEEP_GB", "60"))
     prune_threshold_pct = float(os.getenv("BUILDKIT_PRUNE_THRESHOLD_PCT", "60"))
     # Prune aggressively by default; filters like "unused-for=12h" prevented GC from
@@ -512,6 +643,7 @@ def _chunks(seq: list[str], size: int):
     total_batches = len(batches)
 
     with (
+        _prepare_cached_sdist() as cached_sdist,
         manifest_file.open("w") as writer,
         tqdm(
             total=len(base_images), desc="Building agent-server images", leave=True
@@ -524,72 +656,56 @@ def _chunks(seq: list[str], size: int):
                 continue
 
             logger.info(
-                "Starting batch %d/%d (%d images)", batch_idx, total_batches, len(batch)
+                "Starting batch %d/%d (%d images)",
+                batch_idx,
+                total_batches,
+                len(batch),
+            )
+            in_progress: set[str] = set(batch)
+            _update_pbar(
+                pbar,
+                successes,
+                failures,
+                len(in_progress),
+                next(iter(in_progress), None),
+                f"Batch {batch_idx}/{total_batches} running",
             )
-            in_progress: set[str] = set()
-
-            with ProcessPoolExecutor(max_workers=max_workers) as ex:
-                futures = {}
-                for base in batch:
-                    in_progress.add(base)
-                    resolved_tag = (
-                        base_image_to_custom_tag_fn(base)
-                        if base_image_to_custom_tag_fn
-                        else ""
-                    )
-                    fut = ex.submit(
-                        _build_with_logging,
-                        log_dir=build_log_dir,
-                        base_image=base,
-                        target_image=image,
-                        custom_tag=resolved_tag,
-                        target=target,
-                        push=push,
-                        max_retries=max_retries,
-                        post_build_fn=post_build_fn,
-                    )
-                    futures[fut] = base
 
+            for result in _iter_batch_results(
+                batch=batch,
+                log_dir=build_log_dir,
+                image=image,
+                target=target,
+                push=push,
+                base_image_to_custom_tag_fn=base_image_to_custom_tag_fn,
+                max_workers=max_workers,
+                max_retries=max_retries,
+                post_build_fn=post_build_fn,
+                cached_sdist=cached_sdist,
+            ):
+                status = None
+                writer.write(result.model_dump_json() + "\n")
+                writer.flush()
+
+                with mu:
+                    if result.error or not result.tags:
+                        failures += 1
+                        status = "❌ Failed"
+                    else:
+                        successes += 1
+                        status = "✅ Done"
+
+                in_progress.discard(result.base_image)
+                pbar.update(1)
                 _update_pbar(
                     pbar,
                     successes,
                     failures,
                     len(in_progress),
                     next(iter(in_progress), None),
-                    f"Batch {batch_idx}/{total_batches} running",
+                    status,
                 )
 
-                for fut in as_completed(futures):
-                    base = futures[fut]
-                    status = None
-                    try:
-                        result: BuildOutput = fut.result()
-                    except Exception as e:
-                        logger.error("Build failed for %s: %r", base, e)
-                        result = BuildOutput(base_image=base, tags=[], error=repr(e))
-
-                    writer.write(result.model_dump_json() + "\n")
-                    writer.flush()
-
-                    with mu:
-                        if result.error or not result.tags:
-                            failures += 1
-                            status = "❌ Failed"
-                        else:
-                            successes += 1
-                            status = "✅ Done"
-
-                    in_progress.discard(base)
-                    pbar.update(1)
-                    _update_pbar(
-                        pbar,
-                        successes,
-                        failures,
-                        len(in_progress),
-                        next(iter(in_progress), None),
-                        status,
-                    )
-
             used, total = buildkit_disk_usage()
             if total > 0:
                 logger.info(
@@ -622,10 +738,10 @@ def _chunks(seq: list[str], size: int):
                         total_batches,
                         prune_threshold_pct,
                     )
-    logger.info(
-        "Done. Built=%d  Failed=%d  Manifest=%s",
-        successes,
-        failures,
-        str(manifest_file),
-    )
-    return 1 if failures else 0
+        logger.info(
+            "Done. Built=%d  Failed=%d  Manifest=%s",
+            successes,
+            failures,
+            str(manifest_file),
+        )
+        return 1 if failures else 0
diff --git a/benchmarks/utils/buildx_utils.py b/benchmarks/utils/buildx_utils.py
index 648bb7d25..0a2aa2037 100644
--- a/benchmarks/utils/buildx_utils.py
+++ b/benchmarks/utils/buildx_utils.py
@@ -3,7 +3,10 @@
 Buildx/BuildKit utilities for image build resets and pruning.
 """
 
+# Use stdlib logging instead of openhands.sdk.get_logger to avoid initializing
+# Rich console state before ProcessPoolExecutor forks (causes deadlocks).
 import json
+import logging
 import os
 import re
 import shutil
@@ -11,10 +14,8 @@
 import time
 from pathlib import Path
 
-from openhands.sdk import get_logger
 
-
-logger = get_logger(__name__)
+logger = logging.getLogger(__name__)
 
 
 def _read_reset_state(path: Path) -> dict[str, float]:
diff --git a/benchmarks/utils/image_utils.py b/benchmarks/utils/image_utils.py
index 467074cb9..45c6f770f 100644
--- a/benchmarks/utils/image_utils.py
+++ b/benchmarks/utils/image_utils.py
@@ -1,7 +1,10 @@
 #!/usr/bin/env python3
 from __future__ import annotations
 
+# Use stdlib logging instead of openhands.sdk.get_logger to avoid initializing
+# Rich console state before ProcessPoolExecutor forks (causes deadlocks).
 import base64
+import logging
 import os
 import subprocess
 import sys
@@ -14,10 +17,8 @@
 
 import requests
 
-from openhands.sdk import get_logger
 
-
-logger = get_logger(__name__)
+logger = logging.getLogger(__name__)
 
 
 ACCEPT = ",".join(
diff --git a/tests/test_image_utils.py b/tests/test_image_utils.py
index c46830cb6..82ade18a6 100644
--- a/tests/test_image_utils.py
+++ b/tests/test_image_utils.py
@@ -4,8 +4,10 @@
 which centralize Docker image detection and build logic across all benchmarks.
 """
 
+import contextlib
 import os
 import subprocess
+from pathlib import Path
 from unittest.mock import MagicMock, patch
 
 import pytest
@@ -255,3 +257,97 @@ def test_passes_target_to_build_image(self, mock_build, _mock_exists):
         _, kwargs = mock_build.call_args
         assert kwargs["target"] == "binary"
         assert kwargs["push"] is False
+
+
+class TestCachedSdistReuse:
+    def test_build_image_passes_cached_sdist_to_sdk_build_module(
+        self,
+        tmp_path: Path,
+    ):
+        from benchmarks.utils.build_utils import build_image
+        from openhands.agent_server.docker import build as sdk_build_module
+
+        cached_sdist = tmp_path / "openhands-sdk.tar.gz"
+        cached_sdist.write_text("cached", encoding="utf-8")
+        captured = {}
+
+        def fake_build(opts):
+            captured["prebuilt_sdist"] = opts.prebuilt_sdist
+            return ["integration:test"]
+
+        with (
+            patch(
+                "benchmarks.utils.build_utils.remote_image_exists", return_value=False
+            ),
+            patch(
+                "benchmarks.utils.build_utils._get_sdk_submodule_info",
+                return_value=("main", "abcdef0", "1.0.0"),
+            ),
+            patch.object(sdk_build_module, "build", side_effect=fake_build),
+        ):
+            result = build_image(
+                base_image="base:latest",
+                target_image="ghcr.io/openhands/eval-agent-server",
+                custom_tag="mytag",
+                cached_sdist=cached_sdist,
+            )
+
+        assert result.error is None
+        assert result.tags == ["integration:test"]
+        assert captured["prebuilt_sdist"] == cached_sdist
+
+
+class TestBuildBatchSizeConfig:
+    def test_build_parser_accepts_build_batch_size(self):
+        from benchmarks.utils.build_utils import get_build_parser
+
+        args = get_build_parser().parse_args(["--build-batch-size", "50"])
+
+        assert args.build_batch_size == 50
+
+    @patch.dict(os.environ, {"BUILD_BATCH_SIZE": "99"})
+    def test_build_all_images_prefers_explicit_batch_size_over_env(
+        self,
+        tmp_path: Path,
+    ):
+        from benchmarks.utils import build_utils
+
+        seen_batches: list[list[str]] = []
+
+        @contextlib.contextmanager
+        def fake_prepare_cached_sdist():
+            yield None
+
+        def fake_iter_batch_results(**kwargs):
+            batch = kwargs["batch"]
+            seen_batches.append(list(batch))
+            for base in batch:
+                yield BuildOutput(
+                    base_image=base,
+                    tags=[f"tag:{base}"],
+                    error=None,
+                )
+
+        with (
+            patch.object(
+                build_utils,
+                "_prepare_cached_sdist",
+                side_effect=fake_prepare_cached_sdist,
+            ),
+            patch.object(
+                build_utils,
+                "_iter_batch_results",
+                side_effect=fake_iter_batch_results,
+            ),
+            patch.object(build_utils, "buildkit_disk_usage", return_value=(0, 0)),
+            patch.object(build_utils, "maybe_prune_buildkit_cache", return_value=False),
+        ):
+            exit_code = build_utils.build_all_images(
+                base_images=["base-1", "base-2", "base-3"],
+                target="source-minimal",
+                build_dir=tmp_path,
+                build_batch_size=2,
+            )
+
+        assert exit_code == 0
+        assert seen_batches == [["base-1", "base-2"], ["base-3"]]
diff --git a/vendor/software-agent-sdk b/vendor/software-agent-sdk
index bde715c12..8e8223b24 160000
--- a/vendor/software-agent-sdk
+++ b/vendor/software-agent-sdk
@@ -1 +1 @@
-Subproject commit bde715c12bce8fb112980529d5ad162f6b81a7f1
+Subproject commit 8e8223b24dfd041875fe845b13326b0a1238b793