pip包安装需多次重试才成功是否普遍？跨系统遇此问题求助

这种现象确实不算罕见，尤其是在网络环境不稳定、PyPI源访问受限，或者遇到pip/依赖包本身的版本兼容bug时，很容易出现这类问题。

从你提供的错误日志来看，这次安装失败是因为pip依赖的packaging库出现了内部属性错误（AttributeError: 'Version' object has no attribute '_version'），这属于pip自身依赖的底层库bug，和网络无关，这类偶发的工具链bug也会导致安装失败，重试时可能因为环境状态变化（比如缓存意外清理、依赖临时修复）而成功。

常见的导致pip安装需要多次重试的原因包括：

• 网络波动：PyPI官方源在部分地区访问不稳定，下载包时容易中断，重试几次可能成功
• PyPI源镜像同步延迟：部分镜像源的包版本更新不及时，导致解析依赖时出错
• pip/依赖库版本bug：像你遇到的packaging库属性错误，属于工具链的偶发问题，重试可能避开异常路径
• conda环境冲突：conda和pip的依赖管理逻辑不同，混用可能导致依赖状态混乱，重试时环境状态变化可能解决问题

可以尝试这些方法减少重试次数：

• 切换到稳定的国内PyPI镜像源，比如执行 pip install -i https://pypi.tuna.tsinghua.edu.cn/simple accelerate==0.18.0
• 更新pip到最新版本：pip install --upgrade pip
• 当遇到工具链bug时，尝试清理pip缓存（你已经用了--no-cache），或者临时切换conda环境的pip版本
• 对于特定包，尝试用conda安装替代pip（如果conda仓库有对应版本）：conda install accelerate=0.18.0

示例截图 #

Windows系统下的安装日志示例 #

(textgen) C:\w\RedHeart\text-generation-webui>pip3 install accelerate==0.18.0 --verbose --no-cache

(textgen) C:\w\RedHeart\text-generation-webui>pip3 install accelerate==0.18.0 --verbose --no-cache
Using pip 23.0.1 from C:\Users\levy\miniconda3\envs\textgen\lib\site-packages\pip (python 3.10)
Collecting accelerate==0.18.0
  Downloading accelerate-0.18.0-py3-none-any.whl (215 kB)
     ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 215.3/215.3 kB 13.7 MB/s eta 0:00:00

(textgen) C:\w\RedHeart\text-generation-webui>pip3 install accelerate==0.18.0 --verbose --no-cache
Using pip 23.0.1 from C:\Users\levy\miniconda3\envs\textgen\lib\site-packages\pip (python 3.10)
Collecting accelerate==0.18.0
  Downloading accelerate-0.18.0-py3-none-any.whl (215 kB)
     ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 215.3/215.3 kB ? eta 0:00:00
ERROR: Exception:
Traceback (most recent call last):
  File "C:\Users\levy\miniconda3\envs\textgen\lib\site-packages\pip\_internal\cli\base_command.py", line 160, in exc_logging_wrapper
    status = run_func(*args)
  File "C:\Users\levy\miniconda3\envs\textgen\lib\site-packages\pip\_internal\cli\req_command.py", line 247, in wrapper
    return func(self, options, args)
  File "C:\Users\levy\miniconda3\envs\textgen\lib\site-packages\pip\_internal\commands\install.py", line 419, in run
    requirement_set = resolver.resolve(
  File "C:\Users\levy\miniconda3\envs\textgen\lib\site-packages\pip\_internal\resolution\resolvelib\resolver.py", line 92, in resolve
    result = self._result = resolver.resolve(
  File "C:\Users\levy\miniconda3\envs\textgen\lib\site-packages\pip\_vendor\resolvelib\resolvers.py", line 481, in resolve
    state = resolution.resolve(requirements, max_rounds=max_rounds)
  File "C:\Users\levy\miniconda3\envs\textgen\lib\site-packages\pip\_vendor\resolvelib\resolvers.py", line 373, in resolve
    failure_causes = self._attempt_to_pin_criterion(name)
  File "C:\Users\levy\miniconda3\envs\textgen\lib\site-packages\pip\_vendor\resolvelib\resolvers.py", line 213, in _attempt_to_pin_criterion
    criteria = self._get_updated_criteria(candidate)
  File "C:\Users\levy\miniconda3\envs\textgen\lib\site-packages\pip\_vendor\resolvelib\resolvers.py", line 204, in _get_updated_criteria
    self._add_to_criteria(criteria, requirement, parent=candidate)
  File "C:\Users\levy\miniconda3\envs\textgen\lib\site-packages\pip\_vendor\resolvelib\resolvers.py", line 172, in _add_to_criteria
    if not criterion.candidates:
  File "C:\Users\levy\miniconda3\envs\textgen\lib\site-packages\pip\_vendor\resolvelib\structs.py", line 151, in __bool__
    return bool(self._sequence)
  File "C:\Users\levy\miniconda3\envs\textgen\lib\site-packages\pip\_internal\resolution\resolvelib\found_candidates.py", line 155, in __bool__
    return any(self)
  File "C:\Users\levy\miniconda3\envs\textgen\lib\site-packages\pip\_internal\resolution\resolvelib\found_candidates.py", line 143, in <genexpr>
    return (c for c in iterator if id(c) not in self._incompatible_ids)
  File "C:\Users\levy\miniconda3\envs\textgen\lib\site-packages\pip\_internal\resolution\resolvelib\found_candidates.py", line 44, in _iter_built
    for version, func in infos:
  File "C:\Users\levy\miniconda3\envs\textgen\lib\site-packages\pip\_internal\resolution\resolvelib\factory.py", line 279, in iter_index_candidate_infos
    result = self._finder.find_best_candidate(
  File "C:\Users\levy\miniconda3\envs\textgen\lib\site-packages\pip\_internal\index\package_finder.py", line 896, in find_best_candidate
    return candidate_evaluator.compute_best_candidate(candidates)
  File "C:\Users\levy\miniconda3\envs\textgen\lib\site-packages\pip\_internal\index\package_finder.py", line 579, in compute_best_candidate
    applicable_candidates = self.get_applicable_candidates(candidates)
  File "C:\Users\levy\miniconda3\envs\textgen\lib\site-packages\pip\_internal\index\package_finder.py", line 464, in get_applicable_candidates
    versions = {
  File "C:\Users\levy\miniconda3\envs\textgen\lib\site-packages\pip\_internal\index\package_finder.py", line 464, in <setcomp>
    versions = {
  File "C:\Users\levy\miniconda3\envs\textgen\lib\site-packages\pip\_vendor\packaging\specifiers.py", line 205, in filter
    if self.contains(parsed_version, **kw):
  File "C:\Users\levy\miniconda3\envs\textgen\lib\site-packages\pip\_vendor\packaging\specifiers.py", line 183, in contains
    if normalized_item.is_prerelease and not prereleases:
  File "C:\Users\levy\miniconda3\envs\textgen\lib\site-packages\pip\_vendor\packaging\version.py", line 370, in is_prerelease
    return self.dev is not None or self.pre is not None
  File "C:\Users\levy\miniconda3\envs\textgen\lib\site-packages\pip\_vendor\packaging\version.py", line 342, in dev
    return self._version.dev[1] if self._version.dev else None
AttributeError: 'Version' object has no attribute '_version'

(textgen) C:\w\RedHeart\text-generation-webui>

内容的提问来源于stack exchange，提问作者Levy Moreira