Re: Speeding up VFS using HW assist
Hi! > I will be using Linux as the OS for an embedded system. > I was looking into 2.4.4 kernel code and saw the dcache implementation > in VFS which is pretty neat and fast by itself. > > My question is, will I gain any considerable efficiency in file system > access > if I can move this "pathname -> inode" lookup into some proprietery > HW assist mechanism and take out the dcache hashing and "cached_lookup" > function. I doubt it will do much difference. How much time is spent in kernel in your workload? What kind of embedded system is that? > How good(bad) was it before the dcache implementation and in which release > was dcache feature added (was it only after 2.2.x release). > Did we get 2-3 times better performance with dcache? (if not, how much?) I'd be surprised if dcache made more than 20% speedup. > Can anyone suggest any other place in the file system (VFS and EXT2) where > we > can use any HW assist (let us say FPGA implementing search, lookup, etc.) > to speed up file-system access (both for opening and read/write) Dumping ext2 for reiserfs? ;-) -- Philips Velo 1: 1"x4"x8", 300gram, 60, 12MB, 40bogomips, linux, mutt, details at http://atrey.karlin.mff.cuni.cz/~pavel/velo/index.html. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: Speeding up VFS using HW assist
Hi! I will be using Linux as the OS for an embedded system. I was looking into 2.4.4 kernel code and saw the dcache implementation in VFS which is pretty neat and fast by itself. My question is, will I gain any considerable efficiency in file system access if I can move this pathname - inode lookup into some proprietery HW assist mechanism and take out the dcache hashing and cached_lookup function. I doubt it will do much difference. How much time is spent in kernel in your workload? What kind of embedded system is that? How good(bad) was it before the dcache implementation and in which release was dcache feature added (was it only after 2.2.x release). Did we get 2-3 times better performance with dcache? (if not, how much?) I'd be surprised if dcache made more than 20% speedup. Can anyone suggest any other place in the file system (VFS and EXT2) where we can use any HW assist (let us say FPGA implementing search, lookup, etc.) to speed up file-system access (both for opening and read/write) Dumping ext2 for reiserfs? ;-) -- Philips Velo 1: 1x4x8, 300gram, 60, 12MB, 40bogomips, linux, mutt, details at http://atrey.karlin.mff.cuni.cz/~pavel/velo/index.html. - To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Speeding up VFS using HW assist
Hello All, I will be using Linux as the OS for an embedded system. I was looking into 2.4.4 kernel code and saw the dcache implementation in VFS which is pretty neat and fast by itself. My question is, will I gain any considerable efficiency in file system access if I can move this "pathname -> inode" lookup into some proprietery HW assist mechanism and take out the dcache hashing and "cached_lookup" function. How good(bad) was it before the dcache implementation and in which release was dcache feature added (was it only after 2.2.x release). Did we get 2-3 times better performance with dcache? (if not, how much?) Can anyone suggest any other place in the file system (VFS and EXT2) where we can use any HW assist (let us say FPGA implementing search, lookup, etc.) to speed up file-system access (both for opening and read/write) Would tweaking the buffer cache and page cache sizes make a considerable effect on efficiency? Any other suggestions? Thanks a lot, Bharath - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
