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Nimrod

V2EX 第 357509 号会员,加入于 2018-10-22 08:03:23 +08:00
今日活跃度排名 23711
Nimrod 最近回复了
31 天前
回复了 Kamitora 创建的主题 职场话题 实习一周有感,请求建议。
同上海实习中,研发岗位,真的太累了,甚至考虑少拿点钱轻松一点。🌚
56 天前
回复了 kisshere 创建的主题 程序员 rsync 的-c 和-W 参数的含义到底什么意思?
参见 https://linux.die.net/man/1/rsync
-c, --checksum
This changes the way rsync checks if the files have been changed and are in need of a transfer. Without this option, rsync uses a lqquick checkrq that (by default) checks if each file's size and time of last modification match between the sender and receiver. This option changes this to compare a 128-bit checksum for each file that has a matching size. Generating the checksums means that both sides will expend a lot of disk I/O reading all the data in the files in the transfer (and this is prior to any reading that will be done to transfer changed files), so this can slow things down significantly.
The sending side generates its checksums while it is doing the file-system scan that builds the list of the available files. The receiver generates its checksums when it is scanning for changed files, and will checksum any file that has the same size as the corresponding sender's file: files with either a changed size or a changed checksum are selected for transfer.
Note that rsync always verifies that each transferred file was correctly reconstructed on the receiving side by checking a whole-file checksum that is generated as the file is transferred, but that automatic after-the-transfer verification has nothing to do with this option's before-the-transfer lqDoes this file need to be updated?rq check.
For protocol 30 and beyond (first supported in 3.0.0), the checksum used is MD5. For older protocols, the checksum used is MD4.
-W, --whole-file
With this option rsync's delta-transfer algorithm is not used and the whole file is sent as-is instead. The transfer may be faster if this option is used when the bandwidth between the source and destination machines is higher than the bandwidth to disk (especially when the lqdiskrq is actually a networked filesystem). This is the default when both the source and destination are specified as local paths.

简而言之,-c 是用 checksum 替代默认 rsync 的增量检测算法,-W 不作增量检测算法,直接拷贝。
增量检测是指针对同一个文件,检查有什么修改。
110 天前
回复了 foxyier 创建的主题 Python opencv- Python 翻译中(仅供参考)
@MinQ 大公司还是得用 opencv 的,opencv 有针对各种架构的加速库。
113 天前
回复了 shylockhg 创建的主题 职场话题 24 了,面试腾讯倒在脑经急转弯题上了
脑经×
脑筋✓
113 天前
回复了 morainzh 创建的主题 程序员 介绍一下如何自组 500 以下的机械键盘?
借楼问下,客制相比于厂牌,除了好看,有啥优势吗?
116 天前
回复了 gzxu 创建的主题 V2EX 我被盗号了?
这个连续登陆不是非得每天登陆才能保持的。
118 天前
回复了 Nimrod 创建的主题 上海 上海哪有比较好的按摩店?
@artikle 记得名字吗老铁?
118 天前
回复了 Nimrod 创建的主题 上海 上海哪有比较好的按摩店?
@awesomes 正规的。
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