Thanks，I will adopt it and resubmit.
On Fri, Feb 26, 2021 at 10:50 PM Eric Dumazet <eric.duma...@gmail.com> wrote:
>
>
>
> On 2/26/21 11:57 AM, Yejune Deng wrote:
> > In inet_initpeers(), if si.totalram <= (8192*1024)/PAGE_SIZE, it will
> > be judged three times. Use else if instead of if, it only needs to be
> > judged once.
> >
> > Signed-off-by: Yejune Deng <yejune.d...@gmail.com>
> > ---
> > net/ipv4/inetpeer.c | 10 +++++-----
> > 1 file changed, 5 insertions(+), 5 deletions(-)
> >
> > diff --git a/net/ipv4/inetpeer.c b/net/ipv4/inetpeer.c
> > index ff327a62c9ce..07cd1f8204b3 100644
> > --- a/net/ipv4/inetpeer.c
> > +++ b/net/ipv4/inetpeer.c
> > @@ -81,12 +81,12 @@ void __init inet_initpeers(void)
> > * <kuz...@ms2.inr.ac.ru>. I don't have any opinion about the values
> > * myself. --SAW
> > */
> > - if (si.totalram <= (32768*1024)/PAGE_SIZE)
> > + if (si.totalram <= (8192 * 1024) / PAGE_SIZE)
> > + inet_peer_threshold >>= 4; /* about 128KB */
> > + else if (si.totalram <= (16384 * 1024) / PAGE_SIZE)
> > + inet_peer_threshold >>= 2; /* about 512KB */
> > + else if (si.totalram <= (32768 * 1024) / PAGE_SIZE)
> > inet_peer_threshold >>= 1; /* max pool size about 1MB on IA32
> > */
>
>
> If you really want to change this stuff, I would suggest updating comments,
> because nowadays, struct inet_peer on IA32 uses 128 bytes.
>
> So 32768 entries would consume 4 MB,
> 16384 entries would consume 2 MB
>
> and 4096 entries would consume 512KB
>
> Another idea would be to get rid of the cascade and use something that
> will not need to be adjusted in the future.
>
> diff --git a/net/ipv4/inetpeer.c b/net/ipv4/inetpeer.c
> index
> ff327a62c9ce9b1794104c3c924f5f2b9820ac8b..d5f486bd8c35234f99b22842e756a10531e070d6
> 100644
> --- a/net/ipv4/inetpeer.c
> +++ b/net/ipv4/inetpeer.c
> @@ -65,7 +65,7 @@ EXPORT_SYMBOL_GPL(inet_peer_base_init);
> #define PEER_MAX_GC 32
>
> /* Exported for sysctl_net_ipv4. */
> -int inet_peer_threshold __read_mostly = 65536 + 128; /* start to throw
> entries more
> +int inet_peer_threshold __read_mostly; /* start to throw entries more
> * aggressively at this stage */
> int inet_peer_minttl __read_mostly = 120 * HZ; /* TTL under high load: 120
> sec */
> int inet_peer_maxttl __read_mostly = 10 * 60 * HZ; /* usual time to
> live: 10 min */
> @@ -73,20 +73,13 @@ int inet_peer_maxttl __read_mostly = 10 * 60 * HZ; /*
> usual time to live: 10 min
> /* Called from ip_output.c:ip_init */
> void __init inet_initpeers(void)
> {
> - struct sysinfo si;
> + u64 nr_entries;
>
> - /* Use the straight interface to information about memory. */
> - si_meminfo(&si);
> - /* The values below were suggested by Alexey Kuznetsov
> - * <kuz...@ms2.inr.ac.ru>. I don't have any opinion about the values
> - * myself. --SAW
> - */
> - if (si.totalram <= (32768*1024)/PAGE_SIZE)
> - inet_peer_threshold >>= 1; /* max pool size about 1MB on IA32
> */
> - if (si.totalram <= (16384*1024)/PAGE_SIZE)
> - inet_peer_threshold >>= 1; /* about 512KB */
> - if (si.totalram <= (8192*1024)/PAGE_SIZE)
> - inet_peer_threshold >>= 2; /* about 128KB */
> + /* 1% of physical memory */
> + nr_entries = div64_ul((u64)totalram_pages() << PAGE_SHIFT,
> + 100 * L1_CACHE_ALIGN(sizeof(struct inet_peer)));
> +
> + inet_peer_threshold = clamp_val(nr_entries, 4096, 65536 + 128);
>
> peer_cachep = kmem_cache_create("inet_peer_cache",
> sizeof(struct inet_peer),
>
>
>
>
>
>
