nscd: Improve nscd.conf comments.
Commit Message
This is another patch that attempts to harmonize Fedora with upstream glibc,
and provide some of the same warnings and notes that we have no our nscd.conf
file. I think the note about 'shared' and cache hit rates is particularly
relevant, and we've had users asking us about this for years.
8< --- 8< --- 8<
This change adds a warning to nscd.conf about running multiple caching
services together and that it may lead to unexpected behaviours. Also we
add a note that enabling the 'shared' option will cause cache hit rates
to be misreported (a side effect of the implementation).
---
ChangeLog | 4 ++++
nscd/nscd.conf | 6 ++++++
2 files changed, 10 insertions(+)
Comments
On 3/20/19 10:35 PM, Carlos O'Donell wrote:
> This is another patch that attempts to harmonize Fedora with upstream glibc,
> and provide some of the same warnings and notes that we have no our nscd.conf
> file. I think the note about 'shared' and cache hit rates is particularly
> relevant, and we've had users asking us about this for years.
Ping?
> 8< --- 8< --- 8<
>
> This change adds a warning to nscd.conf about running multiple caching
> services together and that it may lead to unexpected behaviours. Also we
> add a note that enabling the 'shared' option will cause cache hit rates
> to be misreported (a side effect of the implementation).
> ---
> ChangeLog | 4 ++++
> nscd/nscd.conf | 6 ++++++
> 2 files changed, 10 insertions(+)
>
> diff --git a/ChangeLog b/ChangeLog
> index 9765ae0160..a7b90cd1a7 100644
> --- a/ChangeLog
> +++ b/ChangeLog
> @@ -1,3 +1,7 @@
> +2019-03-20 Carlos O'Donell <carlos@redhat.com>
> +
> + * nscd/nscd.conf: Add warning and comment about shared option.
> +
> 2019-03-20 Carlos O'Donell <carlos@redhat.com>
>
> * nss/nsswitch.conf: Expand comments, and simplify defaults.
> diff --git a/nscd/nscd.conf b/nscd/nscd.conf
> index 39b875912d..ec8a8c1622 100644
> --- a/nscd/nscd.conf
> +++ b/nscd/nscd.conf
> @@ -3,6 +3,9 @@
> #
> # An example Name Service Cache config file. This file is needed by nscd.
> #
> +# WARNING: Running nscd with a secondary caching service like sssd may lead to
> +# unexpected behaviour, especially with how long entries are cached.
> +#
> # Legal entries are:
> #
> # logfile <file>
> @@ -23,6 +26,9 @@
> # check-files <service> <yes|no>
> # persistent <service> <yes|no>
> # shared <service> <yes|no>
> +# NOTE: Setting 'shared' to a value of 'yes' will accelerate the lookup
> +# with the help of the client, but these lookups will not be
> +# counted as cache hits i.e. 'nscd -g' may show '0%'.
> # max-db-size <service> <number bytes>
> # auto-propagate <service> <yes|no>
> #
@@ -1,3 +1,7 @@
+2019-03-20 Carlos O'Donell <carlos@redhat.com>
+
+ * nscd/nscd.conf: Add warning and comment about shared option.
+
2019-03-20 Carlos O'Donell <carlos@redhat.com>
* nss/nsswitch.conf: Expand comments, and simplify defaults.
@@ -3,6 +3,9 @@
#
# An example Name Service Cache config file. This file is needed by nscd.
#
+# WARNING: Running nscd with a secondary caching service like sssd may lead to
+# unexpected behaviour, especially with how long entries are cached.
+#
# Legal entries are:
#
# logfile <file>
@@ -23,6 +26,9 @@
# check-files <service> <yes|no>
# persistent <service> <yes|no>
# shared <service> <yes|no>
+# NOTE: Setting 'shared' to a value of 'yes' will accelerate the lookup
+# with the help of the client, but these lookups will not be
+# counted as cache hits i.e. 'nscd -g' may show '0%'.
# max-db-size <service> <number bytes>
# auto-propagate <service> <yes|no>
#