Analysing an effect of buffer capacity and periodic dirty buffer flush on data lifetime

This study analyses an effect of buffer capacity and periodic dirty buffer flush on data lifetime on SSDs equipped with large internal buffer and obtains the following results. First, if the internal buffer exists, the proportion of short-lived data decreases. However, when the dirty buffer flush period is shorter than 30 minutes, even if the buffer size increases to 512 MB, most data still has a short lifetime. Second, when the dirty buffer flush period becomes longer (for example, one day), the proportion of short-lived data decreases rapidly as the buffer size increases. As a result, the accuracy of the existing lifetime prediction policy drops drastically. These results indicate that the lifetime prediction policy should be designed considering the presence of the internal buffer in SSDs and the period of dirty buffer flush.