当你启用离线Gmail时，这项新服务实际上并不会下载你所有的邮件，只是下载了大约10000条。Gmail也有自己的方法来确定它为那些严重的电子邮件爱好者存储了哪些邮件。

Gmail的产品经理托德·杰克逊（Todd Jackson）给CNET的网络软件提供了1万封电子邮件的数据，而从事Gmail工作的谷歌用户也给出了同样的1万封电子邮件的估算，同时解释了他们的“启发式”算法，该算法试图“不下载无趣的对话”

简短的版本：离线Gmail估计一个时间跨度涵盖了大约10000条信息和几乎所有这段时间。它绝对同步任何不太大的标签，最近更新过，并且有一些历史，包括几乎可以保证的星号和草稿部分。它跳过了未贴标签的垃圾和所有垃圾邮件，以及大部分未读的标签。

以下是关于同步方法的较长的官方帖子：

• Synchronization is based on the date of conversati***. The system estimates a period of time to cover (at least 1 week in length) that results in approximately 10,000 messages being downloaded. For an average user, this means Gmail will end up downloading several years of mail.
• Additionally, we'll download any conversation marked with a label that contains less than 200 conversati***, has at least one conversation that has been received in the last 30 days and also has at least one conversation that's outside the estimated time period. For many users, this list of labels will include Starred and Drafts.
• Finally, the system determines a list of labels to exclude conversati*** from being downloaded. For example, Trash and Spam are always in this list, along with any label that contains mostly unread conversati*** (unread count greater than 99%). So, we won't download a conversation if it contains only labels in this list. A typical Trashed message will not be downloaded, but a Trashed message that contains the label "alpha" will.

知道了这一点，我们就有理由清理我们的Gmail账户，并开始用更好的标签系统清空收件箱。

本地仅备份10000封邮件是否只覆盖了收件箱的一部分？Gmail的选择方式如何与你的电子邮件使用相匹配？告诉我们你对评论的看法。

有多少是同步的[离线Gmail谷歌集团]