I guess your problem is similar to caching a local spinning disk using a local SSD, unrelated to iSCSI. I once readabout some solutions, but cannot remember. Maybe googling on "linux cache device" or "block device cache" could help you.
Regards, Ulrich >>> ??? <[email protected]> schrieb am 11.10.2016 um 04:36 in Nachricht <campnguzu9bdmbtpuxtxaaqt7b8eo8uzot+23z5mewa6hwbh...@mail.gmail.com>: > Hi Ulrich, > you maybe misunderstood my purpose, i am not going to do caching on iSCSI > transport layer. > you are right that iSCSI devices can be cached just as normal block > devices are. > indeed a normal block device can be cached using memory to cache the hot > data. > but iscsi driver has differences with normal block device, after all it's a > remote disk. > so i want to use a normal block device to act as a cache disk for iscsi > device besides using the normal memory cache. > do you have any suggestions? > thank you! > > 2016-10-10 21:43 GMT+08:00 Ulrich Windl <[email protected]>: > >> The iSCSI transport layer is definitely the wrong place to do caching! >> iSCSI devices are cached just as normal block devices are (unless you use >> direct I/O). >> >> >>> ??? <[email protected]> schrieb am 10.10.2016 um 11:46 in Nachricht >> <[email protected]>: >> >> > >> > does iSCSI protocol itself or open-source iSCSI implementations like >> > open-iscsi have a cache scheme? >> > >> > since an iscsi initiator may access the same data many times, it does not >> > have to get the data from remote target every time via network. so i am >> > wondering if iSCSI provides a scheme by which clients can use a local >> disk >> > to cache the hot data so that when the accessed data is stored in the >> local >> > cache disk initiator can directly get the data from local disk, just >> like a >> > web browser cache does. does anyone konw about this? >> > >> > how can i implement this? thank you. >> > >> > >> > -- >> > You received this message because you are subscribed to the Google Groups >> > "open-iscsi" group. >> > To unsubscribe from this group and stop receiving emails from it, send an >> > email to [email protected]. >> > To post to this group, send email to [email protected]. >> > Visit this group at https://groups.google.com/group/open-iscsi. >> > For more options, visit https://groups.google.com/d/optout. >> >> >> >> >> -- >> You received this message because you are subscribed to a topic in the >> Google Groups "open-iscsi" group. >> To unsubscribe from this topic, visit https://groups.google.com/d/ >> topic/open-iscsi/uVZSZV1pz1M/unsubscribe. >> To unsubscribe from this group and all its topics, send an email to >> [email protected]. >> To post to this group, send email to [email protected]. >> Visit this group at https://groups.google.com/group/open-iscsi. >> For more options, visit https://groups.google.com/d/optout. >> > > -- > You received this message because you are subscribed to the Google Groups > "open-iscsi" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To post to this group, send email to [email protected]. > Visit this group at https://groups.google.com/group/open-iscsi. > For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups "open-iscsi" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/open-iscsi. For more options, visit https://groups.google.com/d/optout.
