差别
这里会显示出您选择的修订版和当前版本之间的差别。
两侧同时换到之前的修订记录 前一修订版 后一修订版 | 前一修订版 | ||
public:it:misc [2020/12/29 09:58] – [Latency Numbers Every Programmer Should Know] oakfire | public:it:misc [2021/09/09 14:23] (当前版本) – oakfire | ||
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====== 杂项 ====== | ====== 杂项 ====== | ||
- | + | ===== Latency Numbers Every Programmer Should Know ===== | |
- | ===== Generate RSA key ===== | + | * [[https:// |
- | < | + | Latency Comparison Numbers (~2020) |
- | # 生成 RSA 私钥(传统格式的) | + | ---------------------------------- |
- | openssl genrsa | + | L1 cache reference |
- | + | Branch mispredict | |
- | # 生成 RSA 公钥 | + | L2 cache reference |
- | openssl rsa -in rsa_private_key.pem | + | Mutex lock/ |
- | + | Main memory reference | |
- | # 将传统格式的私钥转换成 PKCS#8 格式的 | + | Compress 1K bytes with Zippy |
- | openssl pkcs8 -topk8 -inform PEM -in rsa_private_key.pem | + | Send 2,000 bytes over commodity network |
+ | SSD random read | ||
+ | Read 1 MB sequentially from memory | ||
+ | Round trip within same datacenter | ||
+ | Read 1 MB sequentially from SSD* 49, | ||
+ | Disk seek 2, | ||
+ | Read 1 MB sequentially from disk | ||
+ | Send packet CA-> | ||
+ | |||
+ | Notes | ||
+ | ----- | ||
+ | 1 ns = 10^-9 seconds | ||
+ | 1 us = 10^-6 seconds = 1,000 ns | ||
+ | 1 ms = 10^-3 seconds = 1,000 us = 1,000,000 ns | ||
</ | </ | ||
- | ===== Latency Numbers Every Programmer Should Know ===== | ||
- | * [[https:// | ||
- | * [[https:// | + | * [[https:// |
- | <file text latency.txt> | + | |
Latency Comparison Numbers (~2012) | Latency Comparison Numbers (~2012) | ||
---------------------------------- | ---------------------------------- |