GBase 8a支持sha256的sftp加载性能对比sha1下降情况

GBase 8a新版本支持了sha256，本文介绍从算法角度，sha256和sha1的性能差距。

结论

sha1和sha256从算法角度，性能下降在 20%。

复用UUID

generateStringToHash() with: return UUID_STRING

数据编码长度在 ~36 字符(f5cdcda7-d873-455f-9902-dc9c7894bee0). UUID复用了。

Hash	#1 (ms)	#2 (ms)	#3 (ms)	#4 (ms)	#5 (ms)	Average per 1M (ms)
MD5	649	623	621	624	620	627.4
SHA-1	608	588	630	600	594	604
SHA-256	746	724	741	720	758	737.8
SHA-512	1073	1055	1050	1052	1052	1056.4

复用UUID+时间戳

generateStringToHash() with: return UUID_STRING + System.currentTimeMillis();

数据编码长度 ~49 字符(aa096640-21d6-4f44-9c49-4115d3fa69381468217419114). 包括了时间戳。UUID复用了。

Hash	#1 (ms)	#2 (ms)	#3 (ms)	#4 (ms)	#5 (ms)	Average per 1M (ms)
MD5	751	789	745	806	737	765.6
SHA-1	768	765	694	763	751	748.2
SHA-256	842	876	848	839	850	851
SHA-512	1161	1152	1164	1154	1163	1158.8

计算UUID+时间戳

generateStringToHash() with: return UUID.randomUUID().toString() + System.currentTimeMillis();

字符编码长度 ~49(1af4a3e1-1d92-40e7-8a74-7bb7394211e01468216765464). 每次重新计算UUID.

Hash	#1 (ms)	#2 (ms)	#3 (ms)	#4 (ms)	#5 (ms)	Average per 1M (ms)
MD5	1505	1471	1518	1463	1487	1488.8
SHA-1	1333	1309	1323	1326	1334	1325
SHA-256	1505	1496	1507	1498	1516	1504.4
SHA-512	1834	1827	1833	1836	1857	1837.4

复用UUID+复用UUID

generateStringToHash() with: return UUID_STRING + UUID_STRING;

数据编码长度 ~72 字节(57149cb6-991c-4ffd-9c98-d823ee8a61f757149cb6-991c-4ffd-9c98-d823ee8a61f7)。

Hash	#1 (ms)	#2 (ms)	#3 (ms)	#4 (ms)	#5 (ms)	Average per 1M (ms)
MD5	856	824	876	811	828	839
SHA-1	921	896	970	904	893	916.8
SHA-256	1145	1137	1241	1141	1177	1168.2
SHA-512	1133	1131	1116	1102	1110	1118.4

复用UUID+复用UUID+时间戳

generateStringToHash() with: return UUID_STRING + UUID_STRING + System.currentTimeMillis();

数据编码长度 ~85字符 (759529c5-1f57-4167-b289-899c163c775e759529c5-1f57-4167-b289-899c163c775e1468218673060).

Hash	#1 (ms)	#2 (ms)	#3 (ms)	#4 (ms)	#5 (ms)	Average per 1M (ms)
MD5	1029	1035	1034	1012	1037	1029.4
SHA-1	1008	1016	1027	1007	990	1009.6
SHA-256	1254	1249	1290	1259	1248	1260
SHA-512	1228	1221	1232	1230	1226	1227.4

计算UUID+复用UUID+时间戳

generateStringToHash() with: final String randomUuid = UUID.randomUUID().toString();
return randomUuid + randomUuid + System.currentTimeMillis();

编码长度 ~85 字符(2734b31f-16db-4eba-afd5-121d0670ffa72734b31f-16db-4eba-afd5-121d0670ffa71468217683040). UUID每次重新产生，然后复用.

Hash	#1 (ms)	#2 (ms)	#3 (ms)	#4 (ms)	#5 (ms)	Average per 1M (ms)
MD5	1753	1757	1739	1751	1691	1738.2
SHA-1	1634	1634	1627	1634	1633	1632.4
SHA-256	1962	1956	1988	1988	1924	1963.6
SHA-512	1909	1946	1936	1929	1895	1923

参考

https://automationrhapsody.com/md5-sha-1-sha-256-sha-512-speed-performance/