优化下载性能：移除 SHA256 计算并使用 16MB chunks

- 移除下载后的 SHA256 计算，直接使用 API 返回的 hash 值
- 将 chunk size 从 4MB 调整为 16MB，减少 75% 的 I/O 操作
- 这有助于缓解 ComfyUI 执行期间的卡顿问题

py/services/download_manager.py

@@ -19,7 +19,6 @@ from ..utils.civitai_utils import rewrite_preview_url
 from ..utils.preview_selection import select_preview_media
 from ..utils.utils import sanitize_folder_name
 from ..utils.exif_utils import ExifUtils
-from ..utils.file_utils import calculate_sha256
 from ..utils.metadata_manager import MetadataManager
 from .service_registry import ServiceRegistry
 from .settings_manager import get_settings_manager
@@ -965,11 +964,12 @@ class DownloadManager:
             for download_url in download_urls:
                 use_auth = download_url.startswith("https://civitai.com/api/download/")
                 download_kwargs = {
-                    "progress_callback": lambda progress,
-                    snapshot=None: self._handle_download_progress(
+                    "progress_callback": lambda progress, snapshot=None: (
+                        self._handle_download_progress(
                             progress,
                             progress_callback,
                             snapshot,
+                        )
                     ),
                     "use_auth": use_auth,  # Only use authentication for Civitai downloads
                 }
@@ -1238,7 +1238,8 @@ class DownloadManager:
             entry.file_name = os.path.splitext(os.path.basename(file_path))[0]
             # Update size to actual downloaded file size
             entry.size = os.path.getsize(file_path)
-            entry.sha256 = await calculate_sha256(file_path)
+            # Use SHA256 from API metadata (already set in from_civitai_info)
+            # Do not recalculate to avoid blocking during ComfyUI execution
             entries.append(entry)
 
         return entries

py/services/downloader.py

@@ -44,7 +44,9 @@ class DownloadStreamControl:
         self._event.set()
         self._reconnect_requested = False
         self.last_progress_timestamp: Optional[float] = None
-        self.stall_timeout: float = float(stall_timeout) if stall_timeout is not None else 120.0
+        self.stall_timeout: float = (
+            float(stall_timeout) if stall_timeout is not None else 120.0
+        )
 
     def is_set(self) -> bool:
         return self._event.is_set()
@@ -85,7 +87,9 @@ class DownloadStreamControl:
         self.last_progress_timestamp = timestamp or datetime.now().timestamp()
         self._reconnect_requested = False
 
-    def time_since_last_progress(self, *, now: Optional[float] = None) -> Optional[float]:
+    def time_since_last_progress(
+        self, *, now: Optional[float] = None
+    ) -> Optional[float]:
         if self.last_progress_timestamp is None:
             return None
         reference = now if now is not None else datetime.now().timestamp()
@@ -120,7 +124,7 @@ class Downloader:
     def __init__(self):
         """Initialize the downloader with optimal settings"""
         # Check if already initialized for singleton pattern
-        if hasattr(self, '_initialized'):
+        if hasattr(self, "_initialized"):
             return
         self._initialized = True
 
@@ -131,7 +135,9 @@ class Downloader:
         self._session_lock = asyncio.Lock()
 
         # Configuration
-        self.chunk_size = 4 * 1024 * 1024  # 4MB chunks for better throughput
+        self.chunk_size = (
+            16 * 1024 * 1024
+        )  # 16MB chunks to balance I/O reduction and memory usage
         self.max_retries = 5
         self.base_delay = 2.0  # Base delay for exponential backoff
         self.session_timeout = 300  # 5 minutes
@@ -139,10 +145,10 @@ class Downloader:
 
         # Default headers
         self.default_headers = {
-            'User-Agent': 'ComfyUI-LoRA-Manager/1.0',
+            "User-Agent": "ComfyUI-LoRA-Manager/1.0",
             # Explicitly request uncompressed payloads so aiohttp doesn't need optional
             # decoders (e.g. zstandard) that may be missing in runtime environments.
-            'Accept-Encoding': 'identity',
+            "Accept-Encoding": "identity",
         }
 
     @property
@@ -158,7 +164,7 @@ class Downloader:
     @property
     def proxy_url(self) -> Optional[str]:
         """Get the current proxy URL (initialize if needed)"""
-        if not hasattr(self, '_proxy_url'):
+        if not hasattr(self, "_proxy_url"):
             self._proxy_url = None
         return self._proxy_url
 
@@ -169,14 +175,14 @@ class Downloader:
 
         try:
             settings_manager = get_settings_manager()
-            settings_timeout = settings_manager.get('download_stall_timeout_seconds')
+            settings_timeout = settings_manager.get("download_stall_timeout_seconds")
         except Exception as exc:  # pragma: no cover - defensive guard
             logger.debug("Failed to read stall timeout from settings: %s", exc)
 
         raw_value = (
             settings_timeout
             if settings_timeout not in (None, "")
-            else os.environ.get('COMFYUI_DOWNLOAD_STALL_TIMEOUT')
+            else os.environ.get("COMFYUI_DOWNLOAD_STALL_TIMEOUT")
         )
 
         try:
@@ -191,11 +197,13 @@ class Downloader:
         if self._session is None:
             return True
 
-        if not hasattr(self, '_session_created_at') or self._session_created_at is None:
+        if not hasattr(self, "_session_created_at") or self._session_created_at is None:
             return True
 
         # Refresh if session is older than timeout
-        if (datetime.now() - self._session_created_at).total_seconds() > self.session_timeout:
+        if (
+            datetime.now() - self._session_created_at
+        ).total_seconds() > self.session_timeout:
             return True
 
         return False
@@ -217,12 +225,12 @@ class Downloader:
         # Check for app-level proxy settings
         proxy_url = None
         settings_manager = get_settings_manager()
-        if settings_manager.get('proxy_enabled', False):
-            proxy_host = settings_manager.get('proxy_host', '').strip()
-            proxy_port = settings_manager.get('proxy_port', '').strip()
-            proxy_type = settings_manager.get('proxy_type', 'http').lower()
-            proxy_username = settings_manager.get('proxy_username', '').strip()
-            proxy_password = settings_manager.get('proxy_password', '').strip()
+        if settings_manager.get("proxy_enabled", False):
+            proxy_host = settings_manager.get("proxy_host", "").strip()
+            proxy_port = settings_manager.get("proxy_port", "").strip()
+            proxy_type = settings_manager.get("proxy_type", "http").lower()
+            proxy_username = settings_manager.get("proxy_username", "").strip()
+            proxy_password = settings_manager.get("proxy_password", "").strip()
 
             if proxy_host and proxy_port:
                 # Build proxy URL
@@ -231,37 +239,46 @@ class Downloader:
                 else:
                     proxy_url = f"{proxy_type}://{proxy_host}:{proxy_port}"
 
-                logger.debug(f"Using app-level proxy: {proxy_type}://{proxy_host}:{proxy_port}")
+                logger.debug(
+                    f"Using app-level proxy: {proxy_type}://{proxy_host}:{proxy_port}"
+                )
                 logger.debug("Proxy mode: app-level proxy is active.")
         else:
-            logger.debug("Proxy mode: system-level proxy (trust_env) will be used if configured in environment.")
+            logger.debug(
+                "Proxy mode: system-level proxy (trust_env) will be used if configured in environment."
+            )
         # Optimize TCP connection parameters
         connector = aiohttp.TCPConnector(
             ssl=True,
             limit=8,  # Concurrent connections
             ttl_dns_cache=300,  # DNS cache timeout
             force_close=False,  # Keep connections for reuse
-            enable_cleanup_closed=True
+            enable_cleanup_closed=True,
         )
 
         # Configure timeout parameters
         timeout = aiohttp.ClientTimeout(
             total=None,  # No total timeout for large downloads
             connect=60,  # Connection timeout
-            sock_read=300  # 5 minute socket read timeout
+            sock_read=300,  # 5 minute socket read timeout
         )
 
         self._session = aiohttp.ClientSession(
             connector=connector,
-            trust_env=proxy_url is None,  # Only use system proxy if no app-level proxy is set
-            timeout=timeout
+            trust_env=proxy_url
+            is None,  # Only use system proxy if no app-level proxy is set
+            timeout=timeout,
         )
 
         # Store proxy URL for use in requests
         self._proxy_url = proxy_url
         self._session_created_at = datetime.now()
 
-        logger.debug("Created new HTTP session with proxy settings. App-level proxy: %s, System-level proxy (trust_env): %s", bool(proxy_url), proxy_url is None)
+        logger.debug(
+            "Created new HTTP session with proxy settings. App-level proxy: %s, System-level proxy (trust_env): %s",
+            bool(proxy_url),
+            proxy_url is None,
+        )
 
     def _get_auth_headers(self, use_auth: bool = False) -> Dict[str, str]:
         """Get headers with optional authentication"""
@@ -270,10 +287,10 @@ class Downloader:
         if use_auth:
             # Add CivitAI API key if available
             settings_manager = get_settings_manager()
-            api_key = settings_manager.get('civitai_api_key')
+            api_key = settings_manager.get("civitai_api_key")
             if api_key:
-                headers['Authorization'] = f'Bearer {api_key}'
-                headers['Content-Type'] = 'application/json'
+                headers["Authorization"] = f"Bearer {api_key}"
+                headers["Content-Type"] = "application/json"
 
         return headers
 
@@ -303,7 +320,7 @@ class Downloader:
             Tuple[bool, str]: (success, save_path or error message)
         """
         retry_count = 0
-        part_path = save_path + '.part' if allow_resume else save_path
+        part_path = save_path + ".part" if allow_resume else save_path
 
         # Prepare headers
         headers = self._get_auth_headers(use_auth)
@@ -323,50 +340,71 @@ class Downloader:
                 session = await self.session
                 # Debug log for proxy mode at request time
                 if self.proxy_url:
-                    logger.debug(f"[download_file] Using app-level proxy: {self.proxy_url}")
+                    logger.debug(
+                        f"[download_file] Using app-level proxy: {self.proxy_url}"
+                    )
                 else:
-                    logger.debug("[download_file] Using system-level proxy (trust_env) if configured.")
+                    logger.debug(
+                        "[download_file] Using system-level proxy (trust_env) if configured."
+                    )
 
                 # Add Range header for resume if we have partial data
                 request_headers = headers.copy()
                 if allow_resume and resume_offset > 0:
-                    request_headers['Range'] = f'bytes={resume_offset}-'
+                    request_headers["Range"] = f"bytes={resume_offset}-"
 
                 # Disable compression for better chunked downloads
-                request_headers['Accept-Encoding'] = 'identity'
+                request_headers["Accept-Encoding"] = "identity"
 
-                logger.debug(f"Download attempt {retry_count + 1}/{self.max_retries + 1} from: {url}")
+                logger.debug(
+                    f"Download attempt {retry_count + 1}/{self.max_retries + 1} from: {url}"
+                )
                 if resume_offset > 0:
                     logger.debug(f"Requesting range from byte {resume_offset}")
 
-                async with session.get(url, headers=request_headers, allow_redirects=True, proxy=self.proxy_url) as response:
+                async with session.get(
+                    url,
+                    headers=request_headers,
+                    allow_redirects=True,
+                    proxy=self.proxy_url,
+                ) as response:
                     # Handle different response codes
                     if response.status == 200:
                         # Full content response
                         if resume_offset > 0:
                             # Server doesn't support ranges, restart from beginning
-                            logger.warning("Server doesn't support range requests, restarting download")
+                            logger.warning(
+                                "Server doesn't support range requests, restarting download"
+                            )
                             resume_offset = 0
                             if os.path.exists(part_path):
                                 os.remove(part_path)
                     elif response.status == 206:
                         # Partial content response (resume successful)
-                        content_range = response.headers.get('Content-Range')
+                        content_range = response.headers.get("Content-Range")
                         if content_range:
                             # Parse total size from Content-Range header (e.g., "bytes 1024-2047/2048")
-                            range_parts = content_range.split('/')
+                            range_parts = content_range.split("/")
                             if len(range_parts) == 2:
                                 total_size = int(range_parts[1])
-                        logger.info(f"Successfully resumed download from byte {resume_offset}")
+                        logger.info(
+                            f"Successfully resumed download from byte {resume_offset}"
+                        )
                     elif response.status == 416:
                         # Range not satisfiable - file might be complete or corrupted
                         if allow_resume and os.path.exists(part_path):
                             part_size = os.path.getsize(part_path)
-                            logger.warning(f"Range not satisfiable. Part file size: {part_size}")
+                            logger.warning(
+                                f"Range not satisfiable. Part file size: {part_size}"
+                            )
                             # Try to get actual file size
-                            head_response = await session.head(url, headers=headers, proxy=self.proxy_url)
+                            head_response = await session.head(
+                                url, headers=headers, proxy=self.proxy_url
+                            )
                             if head_response.status == 200:
-                                actual_size = int(head_response.headers.get('content-length', 0))
+                                actual_size = int(
+                                    head_response.headers.get("content-length", 0)
+                                )
                                 if part_size == actual_size:
                                     # File is complete, just rename it
                                     if allow_resume:
@@ -388,21 +426,36 @@ class Downloader:
                             resume_offset = 0
                             continue
                     elif response.status == 401:
-                        logger.warning(f"Unauthorized access to resource: {url} (Status 401)")
-                        return False, "Invalid or missing API key, or early access restriction."
+                        logger.warning(
+                            f"Unauthorized access to resource: {url} (Status 401)"
+                        )
+                        return (
+                            False,
+                            "Invalid or missing API key, or early access restriction.",
+                        )
                     elif response.status == 403:
-                        logger.warning(f"Forbidden access to resource: {url} (Status 403)")
-                        return False, "Access forbidden: You don't have permission to download this file."
+                        logger.warning(
+                            f"Forbidden access to resource: {url} (Status 403)"
+                        )
+                        return (
+                            False,
+                            "Access forbidden: You don't have permission to download this file.",
+                        )
                     elif response.status == 404:
                         logger.warning(f"Resource not found: {url} (Status 404)")
-                        return False, "File not found - the download link may be invalid or expired."
+                        return (
+                            False,
+                            "File not found - the download link may be invalid or expired.",
+                        )
                     else:
-                        logger.error(f"Download failed for {url} with status {response.status}")
+                        logger.error(
+                            f"Download failed for {url} with status {response.status}"
+                        )
                         return False, f"Download failed with status {response.status}"
 
                     # Get total file size for progress calculation (if not set from Content-Range)
                     if total_size == 0:
-                        total_size = int(response.headers.get('content-length', 0))
+                        total_size = int(response.headers.get("content-length", 0))
                         if response.status == 206:
                             # For partial content, add the offset to get total file size
                             total_size += resume_offset
@@ -417,7 +470,7 @@ class Downloader:
 
                     # Stream download to file with progress updates
                     loop = asyncio.get_running_loop()
-                    mode = 'ab' if (allow_resume and resume_offset > 0) else 'wb'
+                    mode = "ab" if (allow_resume and resume_offset > 0) else "wb"
                     control = pause_event
 
                     if control is not None:
@@ -425,7 +478,9 @@ class Downloader:
 
                     with open(part_path, mode) as f:
                         while True:
-                            active_stall_timeout = control.stall_timeout if control else self.stall_timeout
+                            active_stall_timeout = (
+                                control.stall_timeout if control else self.stall_timeout
+                            )
 
                             if control is not None:
                                 if control.is_paused():
@@ -437,7 +492,9 @@ class Downloader:
                                             "Reconnect requested after resume"
                                         )
                                 elif control.consume_reconnect_request():
-                                    raise DownloadRestartRequested("Reconnect requested")
+                                    raise DownloadRestartRequested(
+                                        "Reconnect requested"
+                                    )
 
                             try:
                                 chunk = await asyncio.wait_for(
@@ -466,22 +523,32 @@ class Downloader:
                                 control.mark_progress(timestamp=now.timestamp())
 
                             # Limit progress update frequency to reduce overhead
-                            time_diff = (now - last_progress_report_time).total_seconds()
+                            time_diff = (
+                                now - last_progress_report_time
+                            ).total_seconds()
 
                             if progress_callback and time_diff >= 1.0:
                                 progress_samples.append((now, current_size))
                                 cutoff = now - timedelta(seconds=5)
-                                while progress_samples and progress_samples[0][0] < cutoff:
+                                while (
+                                    progress_samples and progress_samples[0][0] < cutoff
+                                ):
                                     progress_samples.popleft()
 
-                                percent = (current_size / total_size) * 100 if total_size else 0.0
+                                percent = (
+                                    (current_size / total_size) * 100
+                                    if total_size
+                                    else 0.0
+                                )
                                 bytes_per_second = 0.0
                                 if len(progress_samples) >= 2:
                                     first_time, first_bytes = progress_samples[0]
                                     last_time, last_bytes = progress_samples[-1]
                                     elapsed = (last_time - first_time).total_seconds()
                                     if elapsed > 0:
-                                        bytes_per_second = (last_bytes - first_bytes) / elapsed
+                                        bytes_per_second = (
+                                            last_bytes - first_bytes
+                                        ) / elapsed
 
                                 progress_snapshot = DownloadProgress(
                                     percent_complete=percent,
@@ -491,21 +558,23 @@ class Downloader:
                                     timestamp=now.timestamp(),
                                 )
 
-                                await self._dispatch_progress_callback(progress_callback, progress_snapshot)
+                                await self._dispatch_progress_callback(
+                                    progress_callback, progress_snapshot
+                                )
                                 last_progress_report_time = now
 
                     # Download completed successfully
                     # Verify file size integrity before finalizing
-                    final_size = os.path.getsize(part_path) if os.path.exists(part_path) else 0
+                    final_size = (
+                        os.path.getsize(part_path) if os.path.exists(part_path) else 0
+                    )
                     expected_size = total_size if total_size > 0 else None
 
                     integrity_error: Optional[str] = None
                     if final_size <= 0:
                         integrity_error = "Downloaded file is empty"
                     elif expected_size is not None and final_size != expected_size:
-                        integrity_error = (
-                            f"File size mismatch. Expected: {expected_size}, Got: {final_size}"
-                        )
+                        integrity_error = f"File size mismatch. Expected: {expected_size}, Got: {final_size}"
 
                     if integrity_error is not None:
                         logger.error(
@@ -555,7 +624,9 @@ class Downloader:
                         rename_attempt = 0
                         rename_success = False
 
-                        while rename_attempt < max_rename_attempts and not rename_success:
+                        while (
+                            rename_attempt < max_rename_attempts and not rename_success
+                        ):
                             try:
                                 # If the destination file exists, remove it first (Windows safe)
                                 if os.path.exists(save_path):
@@ -566,11 +637,18 @@ class Downloader:
                             except PermissionError as e:
                                 rename_attempt += 1
                                 if rename_attempt < max_rename_attempts:
-                                    logger.info(f"File still in use, retrying rename in 2 seconds (attempt {rename_attempt}/{max_rename_attempts})")
+                                    logger.info(
+                                        f"File still in use, retrying rename in 2 seconds (attempt {rename_attempt}/{max_rename_attempts})"
+                                    )
                                     await asyncio.sleep(2)
                                 else:
-                                    logger.error(f"Failed to rename file after {max_rename_attempts} attempts: {e}")
-                                    return False, f"Failed to finalize download: {str(e)}"
+                                    logger.error(
+                                        f"Failed to rename file after {max_rename_attempts} attempts: {e}"
+                                    )
+                                    return (
+                                        False,
+                                        f"Failed to finalize download: {str(e)}",
+                                    )
 
                         final_size = os.path.getsize(save_path)
 
@@ -583,8 +661,9 @@ class Downloader:
                             bytes_per_second=0.0,
                             timestamp=datetime.now().timestamp(),
                         )
-                        await self._dispatch_progress_callback(progress_callback, final_snapshot)
-
+                        await self._dispatch_progress_callback(
+                            progress_callback, final_snapshot
+                        )
 
                     return True, save_path
 
@@ -597,7 +676,9 @@ class Downloader:
                 DownloadRestartRequested,
             ) as e:
                 retry_count += 1
-                logger.warning(f"Network error during download (attempt {retry_count}/{self.max_retries + 1}): {e}")
+                logger.warning(
+                    f"Network error during download (attempt {retry_count}/{self.max_retries + 1}): {e}"
+                )
 
                 if retry_count <= self.max_retries:
                     # Calculate delay with exponential backoff
@@ -615,7 +696,10 @@ class Downloader:
                     continue
                 else:
                     logger.error(f"Max retries exceeded for download: {e}")
-                    return False, f"Network error after {self.max_retries + 1} attempts: {str(e)}"
+                    return (
+                        False,
+                        f"Network error after {self.max_retries + 1} attempts: {str(e)}",
+                    )
 
             except Exception as e:
                 logger.error(f"Unexpected download error: {e}")
@@ -645,7 +729,7 @@ class Downloader:
         url: str,
         use_auth: bool = False,
         custom_headers: Optional[Dict[str, str]] = None,
-        return_headers: bool = False
+        return_headers: bool = False,
     ) -> Tuple[bool, Union[bytes, str], Optional[Dict]]:
         """
         Download a file to memory (for small files like preview images)
@@ -663,16 +747,22 @@ class Downloader:
             session = await self.session
             # Debug log for proxy mode at request time
             if self.proxy_url:
-                logger.debug(f"[download_to_memory] Using app-level proxy: {self.proxy_url}")
+                logger.debug(
+                    f"[download_to_memory] Using app-level proxy: {self.proxy_url}"
+                )
             else:
-                logger.debug("[download_to_memory] Using system-level proxy (trust_env) if configured.")
+                logger.debug(
+                    "[download_to_memory] Using system-level proxy (trust_env) if configured."
+                )
 
             # Prepare headers
             headers = self._get_auth_headers(use_auth)
             if custom_headers:
                 headers.update(custom_headers)
 
-            async with session.get(url, headers=headers, proxy=self.proxy_url) as response:
+            async with session.get(
+                url, headers=headers, proxy=self.proxy_url
+            ) as response:
                 if response.status == 200:
                     content = await response.read()
                     if return_headers:
@@ -700,7 +790,7 @@ class Downloader:
         self,
         url: str,
         use_auth: bool = False,
-        custom_headers: Optional[Dict[str, str]] = None
+        custom_headers: Optional[Dict[str, str]] = None,
     ) -> Tuple[bool, Union[Dict, str]]:
         """
         Get response headers without downloading the full content
@@ -717,16 +807,22 @@ class Downloader:
             session = await self.session
             # Debug log for proxy mode at request time
             if self.proxy_url:
-                logger.debug(f"[get_response_headers] Using app-level proxy: {self.proxy_url}")
+                logger.debug(
+                    f"[get_response_headers] Using app-level proxy: {self.proxy_url}"
+                )
             else:
-                logger.debug("[get_response_headers] Using system-level proxy (trust_env) if configured.")
+                logger.debug(
+                    "[get_response_headers] Using system-level proxy (trust_env) if configured."
+                )
 
             # Prepare headers
             headers = self._get_auth_headers(use_auth)
             if custom_headers:
                 headers.update(custom_headers)
 
-            async with session.head(url, headers=headers, proxy=self.proxy_url) as response:
+            async with session.head(
+                url, headers=headers, proxy=self.proxy_url
+            ) as response:
                 if response.status == 200:
                     return True, dict(response.headers)
                 else:
@@ -742,7 +838,7 @@ class Downloader:
         url: str,
         use_auth: bool = False,
         custom_headers: Optional[Dict[str, str]] = None,
-        **kwargs
+        **kwargs,
     ) -> Tuple[bool, Union[Dict, str]]:
         """
         Make a generic HTTP request and return JSON response
@@ -763,7 +859,9 @@ class Downloader:
             if self.proxy_url:
                 logger.debug(f"[make_request] Using app-level proxy: {self.proxy_url}")
             else:
-                logger.debug("[make_request] Using system-level proxy (trust_env) if configured.")
+                logger.debug(
+                    "[make_request] Using system-level proxy (trust_env) if configured."
+                )
 
             # Prepare headers
             headers = self._get_auth_headers(use_auth)
@@ -771,10 +869,12 @@ class Downloader:
                 headers.update(custom_headers)
 
             # Add proxy to kwargs if not already present
-            if 'proxy' not in kwargs:
-                kwargs['proxy'] = self.proxy_url
+            if "proxy" not in kwargs:
+                kwargs["proxy"] = self.proxy_url
 
-            async with session.request(method, url, headers=headers, **kwargs) as response:
+            async with session.request(
+                method, url, headers=headers, **kwargs
+            ) as response:
                 if response.status == 200:
                     # Try to parse as JSON, fall back to text
                     try: