Hi, replying to myself...
Miroslav Cimerman <[email protected]> wrote: > > > Jiří Zárevúcky [email protected] wrote: > > > On Fri, Jan 24, 2025, 23:25 Miroslav Cimerman [email protected] wrote: > > > > > Hello, > > > > > > I would be grateful for anyone who has an insight > > > into the ext4 filesystem and/or VFS. > > > > > > It would be great to use the maximum IPC data transfer > > > size (64K). The maximum size ext4 currently allows > > > through is 4K. Would it be ok to just bump the parameters > > > to 64K? > > > > I'm no expert at ext4, but it seems to me that you are increasing > > a parameter of the file system on-disk representation? Does such a > > file system work with other operating systems? > > And the change won't affect file system created by Linux tools, would it? > > > I mostly just would like to demonstrate the performance of my RAID on > some "real" files/workloads, other than raw block read/writes. I would > use it just with mkext4 locally on HelenOS. (but it would probably work > elsewhere, the parameters are read from the superblock...) It doesn't work on other systems, Linux doesn't allow even the filesystem blocksizes to be greater than PAGESIZE, which is 4096. > > Anyway, the reason the IPC transfer is limited in such a way is probably > > because the file system implementation read/writes only a single block > > at a time. The "proper" solution to this would be to check how much of > > the transfer is to a single contiguous region and forward that. Yes, will have to merge the writes to a single one in ext4... > Either way I will get it into my tree, so that I can demonstrate some nice > features of HelenRAID. But is there a chance my addition could get merged > into upstream:master? Can I open a PR? It is a stupid idea to put it into upstream, but still, if I or anyone, doesn't find a way to make it use the whole IPC transfer size, I will use that diff just for some performance evaluation. -- mc _______________________________________________ HelenOS-devel mailing list [email protected] http://lists.modry.cz/listinfo/helenos-devel
