{"id":104635,"date":"2022-07-12T09:36:46","date_gmt":"2022-07-12T07:36:46","guid":{"rendered":"https:\/\/prohoster.info\/blog\/novosti-interneta\/dlya-yadra-linux-predlozhena-realizacziya-funkczii-memchr-rabotayushhaya-do-4-raz-bystree"},"modified":"2022-07-12T09:36:46","modified_gmt":"2022-07-12T07:36:46","slug":"dlya-yadra-linux-predlozhena-realizacziya-funkczii-memchr-rabotayushhaya-do-4-raz-bystree","status":"publish","type":"post","link":"https:\/\/prohoster.info\/da\/blog\/news\/dlya-yadra-linux-predlozhena-realizacziya-funkczii-memchr-rabotayushhaya-do-4-raz-bystree","title":{"rendered":"Der er foresl\u00e5et en implementering af funktionen memchr for Linux-kernen, der fungerer op til 4 gange hurtigere.","gt_translate_keys":[{"key":"rendered","format":"text"}]},"content":{"rendered":"
For inclusion in the Linux kernel, a set of patches has been proposed featuring an optimized implementation of the memchr() function, used for character searching in arrays. Unlike the older version, which employed byte-by-byte comparison, the proposed implementation is designed to fully utilize 64- and 32-bit CPU registers. Instead of bytes, comparison is made using machine words, allowing for the comparison of at least 4 bytes at once. <\/p>\n
When searching in large strings, the new variant has proven to be about 4 times faster than the old one (for example, with strings of 1000 characters). For smaller strings, the efficiency of the new implementation isn't as significant but is still higher compared to the original. In the Linux kernel, the size of strings processed in memchr() can reach 512 bytes. The performance gain for 512-byte strings, in cases where the sought character is located at the end of the string, is about 20%. <\/p>\n
Test af kerne 5.18 med den nye variant af «memchr()» til 32- og 64-bit arkitekturer har ikke afsl\u00f8ret nogen problemer. Den overordnede pr\u00e6stationsforbedring af kernelens subsystemer ved brug af den optimerede variant af «memchr()» er endnu ikke blevet vurderet, ligesom n\u00f8dvendigheden af at erstatte implementeringen heller ikke er blevet analyseret (i kernelkoden kaldes funktionen memchr() 129 gange, herunder i driver- og filsystemkoden). \n Kilde: opennet.ru<\/a> <\/p>","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"excerpt":{"rendered":"