花时间的不是下载，而是验证和建立索引。
It's not the downloading that takes the time, it's verifying and indexing it.
从带宽上说，它比下载一个压缩包更高效。比特币只下载 blk0001.dat 里的数据，目前是 55MB，然后自行构建 blkindex.dat，为 47MB。构建 blkindex.dat 才是全部磁盘活动的来源。
Bandwidthwise, it's more efficient than if you downloaded an archive. Bitcoin only downloads the data in blk0001.dat, which is currently 55MB, and builds blkindex.dat itself, which is 47MB. Building blkindex.dat is what causes all the disk activity.
在区块下载期间，它每 500 个区块才把数据库刷一次盘。你可能会看到区块计数在 ??499 和 ??999 处停顿。那就是在刷盘。
During the block download, it only flushes the database to disk every 500 blocks. You may see the block count pause at ??499 and ??999. That's when it's flushing.
自己做验证和建索引，是确保索引数据安全的唯一办法。如果从一个不受信任的来源复制 blk0001.dat 和 blkindex.dat，就无法知道里面的全部内容是否可信。
Doing your own verifying and indexing is the only way to be sure your index data is secure. If you copy blk0001.dat and blkindex.dat from an untrusted source, there's no way to know if you can trust all the contents in them.
也许 Berkeley DB 有一些可调的开关，能启用或加大缓存内存。
Maybe Berkeley DB has some tweaks we can make to enable or increase cache memory.
当前版本尚未建立逐条校对状态记录。来源核验、历史审校与当前译文校对是不同事项。
译文内容版本：f5dfe509ee9f。用于比对文本，不代表校对等级或更新时间。
请填写对应原文、现译文、建议译法和理由。复制后通过你联系本站作者的渠道提交；此处不会自动发送。
