红帽全球峰会第 1 章 alt-java概述
红帽软件包包含对 SSB 漏洞的缓解方案，采用 java 二进制文件的补丁形式。此补丁禁用 x86-64 (Intel 和 AMD)处理器中存在的优化。禁用该优化会降低内核侧通道攻击的风险，但也会降低 CPU 性能。
由于补丁降低了性能，它已从 java 启动程序中删除。现在提供了一个新的二进制 alt-java。在 2021 年 1 月的补丁更新版本(1.8.0 282.b08、11.0.10.9)）中 ，alt-java 二进制文件包含在红帽构建的 OpenJDK 17 和 Red Hat build of OpenJDK 11 GA RPM 软件包中。
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