Jeff Layton <jlayton@xxxxxxxxxx> wrote: > Since most cookies are fairly small, is there any real benefit to > optimizing for length here? How much inflation are we talking about? Taking AFS as an example, a vnode is represented at the file level by two numbers: a 32-bit or 96-bit file ID and a 32-bit uniquifier. If it's a 96-bit file ID, a lot of the time, the upper 64-bits will be zero, so we're talking something like: S421d4,1f07f34,, instead of: S000421d401f07f340000000000000000 or: E0AAQh1AHwfzQAAAAAAAAAAA== The first makes for a more readable name in the cache. The real fun is with NFS, where the name can be very long. For one that's just 5 words in length: T81010001,1,20153e2,,a906194b instead of: T8101000100000001020153e200000000a906194b or: E0gQEAAQAAAAECAVPiAAAAAKkGGUs= (The letter on the front represents the encoding scheme; in the base64 encoding the second digit indicates the amount of padding). I don't know how much difference it makes to the backing filesystem's directory packing - and it may depend on the particular filesystem. David -- Linux-cachefs mailing list Linux-cachefs@xxxxxxxxxx https://listman.redhat.com/mailman/listinfo/linux-cachefs
