Zero-content augmented caches
Zero-content augmented caches
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零内容增强缓存
DOI：
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发表时间：
2009
期刊：
影响因子：
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通讯作者：
André Seznec
中科院分区：
文献类型：
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作者：
J. Dusser;T. Piquet;André Seznec
已经观察到，某些应用程序会操纵大量的空数据。此外，这些零数据通常显示出很高的空间位置。在某些应用程序上，超过20％的数据访问涉及零数据块。在标准高速缓存线上表示缓存中的空块似乎是浪费资源。在本文中，我们提出了零含量增强缓存，即ZCA缓存。 ZCA缓存由一个传统的缓存组成，该缓存带有专门的缓存，用于记住空块，零含有缓存或ZC缓存。在ZC缓存中，数据块由其地址标签和有效性位表示。此外，由于空块通常表现出较高的空间位置，因此可以与ZC缓存中的单个地址标签相关联。例如，ZC缓存映射32MB的零64字节线使用少于80kb的存储空间。空块的解压缩非常简单，因此在ZCA缓存上读取访问时间与常规缓存的范围相同。在操纵大量零数据块的应用程序上，这种ZC缓存可以显着降低错过率和内存流量，从而增加小型硬件开销的性能。特别是，零块上的写入流量有限。对于低零阻滞速率的应用，未观察到性能损失。
It has been observed that some applications manipulate large amounts of null data. Moreover these zero data often exhibit high spatial locality. On some applications more than 20% of the data accesses concern null data blocks. Representing a null block in a cache on a standard cache line appears as a waste of resources. In this paper, we propose the Zero-Content Augmented cache, the ZCA cache. A ZCA cache consists of a conventional cache augmented with a specialized cache for memorizing null blocks, the Zero-Content cache or ZC cache. In the ZC cache, the data block is represented by its address tag and a validity bit. Moreover, as null blocks generally exhibit high spatial locality, several null blocks can be associated with a single address tag in the ZC cache. For instance, a ZC cache mapping 32MB of zero 64-byte lines uses less than 80KB of storage. Decompression of a null block is very simple, therefore read access time on the ZCA cache is in the same range as the one of a conventional cache. On applications manipulating large amount of null data blocks, such a ZC cache allows to significantly reduce the miss rate and memory traffic, and therefore to increase performance for a small hardware overhead. In particular, the write-back traffic on null blocks is limited. For applications with a low null block rate, no performance loss is observed.