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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 | ||
|---|---|---|---|
| 行 1: | 行 1: | ||
| ====== 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) | ||
| ---------------------------------- | ---------------------------------- | ||