> > Basic question. Do you have any performance gain or improvement? > In my test environment. no performance gain. Yes I know it's not for > performance improvement. My understanding: If BKOPS feature is not enabled, the background operations will be started when card handles some read or write command. This will impact read/write performance. If BKOPS is enabled, driver can check whether need to do a BKOPS each time after card handled a read/write command. If need, driver can start BKOPS as soon as possible when user request is empty. This will can improve read/write performance. So I think, anyhow background operations can improve the performance, but only can be seen when your test card need to do a background operations. If your card needn't, there will be no performance gain I think. Driver will works as normal. BTW, the BKOPS is an operational features for eMMC4.41 card, to ensure whether the card support this feature, check ext_csd[502]. > > How to measure or check it has some improvement? > Any ideas? > Right now I didn't know how to do a precise measurement. Maybe keep on transferring large data for a long time with a card which enabled/or not the BKOPS feature can help to get some measurement data. Thanks Chuanxiao ÿô.nÇ·®+%˱é¥wÿº{.nÇ·¥{±þiþ)íèjg¬±¨¶Ýjÿ¾«þG«é¸¢·¦j:+v¨wèm¶ÿþø®w¥þ࣢·hâÿÙ