> On 2020-02-05, lijiang <lijiang@xxxxxxxxxx> wrote: >> Do you have any suggestions about the size of CONFIG_LOG_* and >> CONFIG_PRINTK_* options by default? > > The new printk implementation consumes more than double the memory that > the current printk implementation requires. This is because dictionaries > and meta-data are now stored separately. > > If the old defaults (LOG_BUF_SHIFT=17 LOG_CPU_MAX_BUF_SHIFT=12) were > chosen because they are maximally acceptable defaults, then the defaults > should be reduced by 1 so that the final size is "similar" to the > current implementation. > > If instead the defaults are left as-is, a machine with less than 64 CPUs > will reserve 336KiB for printk information (128KiB text, 128KiB > dictionary, 80KiB meta-data). > > It might also be desirable to reduce the dictionary size (maybe 1/4 the > size of text?). However, since the new printk implementation allows for > non-intrusive dictionaries, we might see their usage increase and start > to be as large as the messages themselves. > > John Ogness > Thanks for the explanation in detail. Lianbo _______________________________________________ kexec mailing list kexec@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/kexec
