| Message ID | 20220311190617.3294919-8-tbecker@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Introduce nfs-readahead-udev | expand |
On 3/11/22 2:06 PM, Thiago Becker wrote: > Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1946283 > Signed-off-by: Thiago Becker <tbecker@redhat.com> > --- > tools/nfs-readahead-udev/Makefile.am | 2 + > .../nfs-readahead-udev/nfs-readahead-udev.man | 47 +++++++++++++++++++ > tools/nfs-readahead-udev/readahead.conf | 14 ++++++ > 3 files changed, 63 insertions(+) > create mode 100644 tools/nfs-readahead-udev/nfs-readahead-udev.man > > diff --git a/tools/nfs-readahead-udev/Makefile.am b/tools/nfs-readahead-udev/Makefile.am > index 010350aa..eaa9b90e 100644 > --- a/tools/nfs-readahead-udev/Makefile.am > +++ b/tools/nfs-readahead-udev/Makefile.am > @@ -10,6 +10,8 @@ udev_rules_DATA = 99-nfs_bdi.rules > ra_confdir = $(sysconfdir) > ra_conf_DATA = readahead.conf > > +man5_MANS = nfs-readahead-udev.man > + > 99-nfs_bdi.rules: 99-nfs_bdi.rules.in $(builddefs) > $(SED) "s|_libexecdir_|@libexecdir@|g" 99-nfs_bdi.rules.in > $@ > > diff --git a/tools/nfs-readahead-udev/nfs-readahead-udev.man b/tools/nfs-readahead-udev/nfs-readahead-udev.man > new file mode 100644 > index 00000000..2477d5b3 > --- /dev/null > +++ b/tools/nfs-readahead-udev/nfs-readahead-udev.man > @@ -0,0 +1,47 @@ > +.\" Manpage for nfs-readahead-udev. > +.nh > +.ad l > +.TH man 5 "08 Mar 2022" "1.0" "nfs-readahead-udev man page" > +.SH NAME > + > +nfs-readahead-udev \- Find the readahead for a given NFS mount > + > +.SH SYNOPSIS > + > +nfs-readahead-udev <device> > + > +.SH DESCRIPTION > + > +\fInfs-readahead-udev\fR is a tool intended to be used with udev to set the \fIread_ahead_kb\fR parameter of NFS mounts, according to the configuration file (see \fICONFIGURATION\fR). \fIdevice\fR is the device number for the NFS backing device as provided by the kernel. > + > +.SH CONFIGURATION > + > +The configuration file (\fI/etc/readahead.conf\fR) contains the readahead configuration, and is formatted as follows. > + > +<LINES> ::= <LINES> <LINE> | <LINE> > + > +<LINE> ::= <TOKENS> <ENDL> > + > +<TOKENS> ::= <TOKENS> <TOKEN> | <TOKEN> > + > +<TOKEN> ::= default | <PAIR> > + > +<PAIR> ::= mountpoint = <mountpoint> | fstype = <nfs|nfs4> | readahead = <readahead> > + > +\fImountpoint\fR is the path in the system where the file system is mounted. > + > +\fIreadahead\fR is an integer to readahead. > + > +\fIfstype\fR is either \fInfs\fR or \fInfs4\fR. > + > +.SH SEE ALSO > + > +mount.nfs(8), nfs(5), udev(7), bcc-readahead(8) > + > +.SH BUGS > + > +No known bugs. > + > +.SH AUTHOR I think it might make sense to added some examples on how the command will be used. > + > +Thiago Rafael Becker <trbecker@gmail.com> > diff --git a/tools/nfs-readahead-udev/readahead.conf b/tools/nfs-readahead-udev/readahead.conf > index 988b30c7..bce830f1 100644 > --- a/tools/nfs-readahead-udev/readahead.conf > +++ b/tools/nfs-readahead-udev/readahead.conf > @@ -1 +1,15 @@ > +# nfs-readahead-udev configuration file. > +# > +# This file configures the readahead for nfs mounts when those are anounced by the kernel. > +# The file is composed on lines that can contain either the default configuration (applied to > +# any nfs mount that does not match any of the other lines) or a combination of > +# mountpoint=<mountpoint> where mountpoint is the mount point for the file system > +# fstype=<nfs|nfs4> specifies that this configuration should only apply to a specific nfs > +# version. > +# Every line must contain a readahead option, with the expected readahead value. > default readahead=128 > + > +# mountpoint=/mnt readahead=4194304 > +# fstype=nfs readahead=4194304 > +# fstype=nfs4 readahead=4194304 > +# mountpoint=/mnt fstype=nfs4 readahead=4194304 Would it make sense to try added these to nfs.conf? I must admin I'm a bit impressed with your lex and yacc routines in patch 5, I have not seen those in a while.. but that does add more dependencies to nfs-utils and as well as yet another config file to manage. steved.
Thanks for the comments. On Thu, Mar 17, 2022 at 12:37 PM Steve Dickson <steved@redhat.com> wrote: > I think it might make sense to added some examples > on how the command will be used. Will do. > Would it make sense to try added these to nfs.conf? > > I must admin I'm a bit impressed with your lex and > yacc routines in patch 5, I have not seen those > in a while.. but that does add more dependencies > to nfs-utils and as well as yet another config file > to manage. I debated with a funko pop between writing the parser and using a parser builder. Originally, the idea was to provide more possibilities, like configuring the read ahead of other devices, but those BDIs don't announce themselves when they are added like NFS does. I also don't know how useful it would be. So this idea is scrapped for now. Here are the debate conclusions: - writing the parser would add some complexity that lex/yacc handles - lex/yacc add build time dependencies and some bloat - error handling is painful with lex/yacc - lex/yacc are well known - using a parser combinator would be my preference, but I couldn't find any written in c that didn't add a new library to the systems It seemed to me that using lex/yacc was the best choice taking into account the needs of both limited storage systems and large servers. I can still see some configurations that may be added in the future, like setting the read ahead per server, network segment, but I believe that the configurations we have cover most of the use cases. I've added a new configuration because I planned to have a more fine grained configuration for multiple file systems/designs, and that would add a lot in nfs.conf (and tie the tool to nfs). And, to be completely honest, I took what I've done in https://github.com/trbecker/readahead-utils and ported it to nfs-utils. That's the history so far. I don't mind taking stuff out if it would make the software more maintainable. > steved. > thiago
diff --git a/tools/nfs-readahead-udev/Makefile.am b/tools/nfs-readahead-udev/Makefile.am index 010350aa..eaa9b90e 100644 --- a/tools/nfs-readahead-udev/Makefile.am +++ b/tools/nfs-readahead-udev/Makefile.am @@ -10,6 +10,8 @@ udev_rules_DATA = 99-nfs_bdi.rules ra_confdir = $(sysconfdir) ra_conf_DATA = readahead.conf +man5_MANS = nfs-readahead-udev.man + 99-nfs_bdi.rules: 99-nfs_bdi.rules.in $(builddefs) $(SED) "s|_libexecdir_|@libexecdir@|g" 99-nfs_bdi.rules.in > $@ diff --git a/tools/nfs-readahead-udev/nfs-readahead-udev.man b/tools/nfs-readahead-udev/nfs-readahead-udev.man new file mode 100644 index 00000000..2477d5b3 --- /dev/null +++ b/tools/nfs-readahead-udev/nfs-readahead-udev.man @@ -0,0 +1,47 @@ +.\" Manpage for nfs-readahead-udev. +.nh +.ad l +.TH man 5 "08 Mar 2022" "1.0" "nfs-readahead-udev man page" +.SH NAME + +nfs-readahead-udev \- Find the readahead for a given NFS mount + +.SH SYNOPSIS + +nfs-readahead-udev <device> + +.SH DESCRIPTION + +\fInfs-readahead-udev\fR is a tool intended to be used with udev to set the \fIread_ahead_kb\fR parameter of NFS mounts, according to the configuration file (see \fICONFIGURATION\fR). \fIdevice\fR is the device number for the NFS backing device as provided by the kernel. + +.SH CONFIGURATION + +The configuration file (\fI/etc/readahead.conf\fR) contains the readahead configuration, and is formatted as follows. + +<LINES> ::= <LINES> <LINE> | <LINE> + +<LINE> ::= <TOKENS> <ENDL> + +<TOKENS> ::= <TOKENS> <TOKEN> | <TOKEN> + +<TOKEN> ::= default | <PAIR> + +<PAIR> ::= mountpoint = <mountpoint> | fstype = <nfs|nfs4> | readahead = <readahead> + +\fImountpoint\fR is the path in the system where the file system is mounted. + +\fIreadahead\fR is an integer to readahead. + +\fIfstype\fR is either \fInfs\fR or \fInfs4\fR. + +.SH SEE ALSO + +mount.nfs(8), nfs(5), udev(7), bcc-readahead(8) + +.SH BUGS + +No known bugs. + +.SH AUTHOR + +Thiago Rafael Becker <trbecker@gmail.com> diff --git a/tools/nfs-readahead-udev/readahead.conf b/tools/nfs-readahead-udev/readahead.conf index 988b30c7..bce830f1 100644 --- a/tools/nfs-readahead-udev/readahead.conf +++ b/tools/nfs-readahead-udev/readahead.conf @@ -1 +1,15 @@ +# nfs-readahead-udev configuration file. +# +# This file configures the readahead for nfs mounts when those are anounced by the kernel. +# The file is composed on lines that can contain either the default configuration (applied to +# any nfs mount that does not match any of the other lines) or a combination of +# mountpoint=<mountpoint> where mountpoint is the mount point for the file system +# fstype=<nfs|nfs4> specifies that this configuration should only apply to a specific nfs +# version. +# Every line must contain a readahead option, with the expected readahead value. default readahead=128 + +# mountpoint=/mnt readahead=4194304 +# fstype=nfs readahead=4194304 +# fstype=nfs4 readahead=4194304 +# mountpoint=/mnt fstype=nfs4 readahead=4194304
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1946283 Signed-off-by: Thiago Becker <tbecker@redhat.com> --- tools/nfs-readahead-udev/Makefile.am | 2 + .../nfs-readahead-udev/nfs-readahead-udev.man | 47 +++++++++++++++++++ tools/nfs-readahead-udev/readahead.conf | 14 ++++++ 3 files changed, 63 insertions(+) create mode 100644 tools/nfs-readahead-udev/nfs-readahead-udev.man