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From: Yu Zhao <yuzhao@google.com>
Date: Mon, 18 Dec 2023 20:44:21 -0700
Message-ID: <CAOUHufbRq8WsGzNRn119GqL5AmeSOkZxQv3L2LTaCm=k3bzrRA@mail.gmail.com>
Subject: Re: [PATCH mm-unstable v1 1/4] mm/mglru: fix underprotected page cache
To: Kairui Song <ryncsn@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>, linux-mm@kvack.org, 
	linux-kernel@vger.kernel.org, Charan Teja Kalla <quic_charante@quicinc.com>, 
	Kalesh Singh <kaleshsingh@google.com>, stable@vger.kernel.org
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable

On Mon, Dec 18, 2023 at 8:21=E2=80=AFPM Yu Zhao <yuzhao@google.com> wrote:
>
> On Mon, Dec 18, 2023 at 11:05=E2=80=AFAM Kairui Song <ryncsn@gmail.com> w=
rote:
> >
> > Yu Zhao <yuzhao@google.com> =E4=BA=8E2023=E5=B9=B412=E6=9C=8815=E6=97=
=A5=E5=91=A8=E4=BA=94 12:56=E5=86=99=E9=81=93=EF=BC=9A
> > >
> > > On Thu, Dec 14, 2023 at 04:51:00PM -0700, Yu Zhao wrote:
> > > > On Thu, Dec 14, 2023 at 11:38=E2=80=AFAM Kairui Song <ryncsn@gmail.=
com> wrote:
> > > > >
> > > > > Yu Zhao <yuzhao@google.com> =E4=BA=8E2023=E5=B9=B412=E6=9C=8814=
=E6=97=A5=E5=91=A8=E5=9B=9B 11:09=E5=86=99=E9=81=93=EF=BC=9A
> > > > > > On Wed, Dec 13, 2023 at 12:59:14AM -0700, Yu Zhao wrote:
> > > > > > > On Tue, Dec 12, 2023 at 8:03=E2=80=AFPM Kairui Song <ryncsn@g=
mail.com> wrote:
> > > > > > > >
> > > > > > > > Kairui Song <ryncsn@gmail.com> =E4=BA=8E2023=E5=B9=B412=E6=
=9C=8812=E6=97=A5=E5=91=A8=E4=BA=8C 14:52=E5=86=99=E9=81=93=EF=BC=9A
> > > > > > > > >
> > > > > > > > > Yu Zhao <yuzhao@google.com> =E4=BA=8E2023=E5=B9=B412=E6=
=9C=8812=E6=97=A5=E5=91=A8=E4=BA=8C 06:07=E5=86=99=E9=81=93=EF=BC=9A
> > > > > > > > > >
> > > > > > > > > > On Fri, Dec 8, 2023 at 1:24=E2=80=AFAM Kairui Song <ryn=
csn@gmail.com> wrote:
> > > > > > > > > > >
> > > > > > > > > > > Yu Zhao <yuzhao@google.com> =E4=BA=8E2023=E5=B9=B412=
=E6=9C=888=E6=97=A5=E5=91=A8=E4=BA=94 14:14=E5=86=99=E9=81=93=EF=BC=9A
> > > > > > > > > > > >
> > > > > > > > > > > > Unmapped folios accessed through file descriptors c=
an be
> > > > > > > > > > > > underprotected. Those folios are added to the oldes=
t generation based
> > > > > > > > > > > > on:
> > > > > > > > > > > > 1. The fact that they are less costly to reclaim (n=
o need to walk the
> > > > > > > > > > > >    rmap and flush the TLB) and have less impact on =
performance (don't
> > > > > > > > > > > >    cause major PFs and can be non-blocking if neede=
d again).
> > > > > > > > > > > > 2. The observation that they are likely to be singl=
e-use. E.g., for
> > > > > > > > > > > >    client use cases like Android, its apps parse co=
nfiguration files
> > > > > > > > > > > >    and store the data in heap (anon); for server us=
e cases like MySQL,
> > > > > > > > > > > >    it reads from InnoDB files and holds the cached =
data for tables in
> > > > > > > > > > > >    buffer pools (anon).
> > > > > > > > > > > >
> > > > > > > > > > > > However, the oldest generation can be very short li=
ved, and if so, it
> > > > > > > > > > > > doesn't provide the PID controller with enough time=
 to respond to a
> > > > > > > > > > > > surge of refaults. (Note that the PID controller us=
es weighted
> > > > > > > > > > > > refaults and those from evicted generations only ta=
ke a half of the
> > > > > > > > > > > > whole weight.) In other words, for a short lived ge=
neration, the
> > > > > > > > > > > > moving average smooths out the spike quickly.
> > > > > > > > > > > >
> > > > > > > > > > > > To fix the problem:
> > > > > > > > > > > > 1. For folios that are already on LRU, if they can =
be beyond the
> > > > > > > > > > > >    tracking range of tiers, i.e., five accesses thr=
ough file
> > > > > > > > > > > >    descriptors, move them to the second oldest gene=
ration to give them
> > > > > > > > > > > >    more time to age. (Note that tiers are used by t=
he PID controller
> > > > > > > > > > > >    to statistically determine whether folios access=
ed multiple times
> > > > > > > > > > > >    through file descriptors are worth protecting.)
> > > > > > > > > > > > 2. When adding unmapped folios to LRU, adjust the p=
lacement of them so
> > > > > > > > > > > >    that they are not too close to the tail. The eff=
ect of this is
> > > > > > > > > > > >    similar to the above.
> > > > > > > > > > > >
> > > > > > > > > > > > On Android, launching 55 apps sequentially:
> > > > > > > > > > > >                            Before     After      Ch=
ange
> > > > > > > > > > > >   workingset_refault_anon  25641024   25598972   0%
> > > > > > > > > > > >   workingset_refault_file  115016834  106178438  -8=
%
> > > > > > > > > > >
> > > > > > > > > > > Hi Yu,
> > > > > > > > > > >
> > > > > > > > > > > Thanks you for your amazing works on MGLRU.
> > > > > > > > > > >
> > > > > > > > > > > I believe this is the similar issue I was trying to r=
esolve previously:
> > > > > > > > > > > https://lwn.net/Articles/945266/
> > > > > > > > > > > The idea is to use refault distance to decide if the =
page should be
> > > > > > > > > > > place in oldest generation or some other gen, which p=
er my test,
> > > > > > > > > > > worked very well, and we have been using refault dist=
ance for MGLRU in
> > > > > > > > > > > multiple workloads.
> > > > > > > > > > >
> > > > > > > > > > > There are a few issues left in my previous RFC series=
, like anon pages
> > > > > > > > > > > in MGLRU shouldn't be considered, I wanted to collect=
 feedback or test
> > > > > > > > > > > cases, but unfortunately it seems didn't get too much=
 attention
> > > > > > > > > > > upstream.
> > > > > > > > > > >
> > > > > > > > > > > I think both this patch and my previous series are fo=
r solving the
> > > > > > > > > > > file pages underpertected issue, and I did a quick te=
st using this
> > > > > > > > > > > series, for mongodb test, refault distance seems stil=
l a better
> > > > > > > > > > > solution (I'm not saying these two optimization are m=
utually exclusive
> > > > > > > > > > > though, just they do have some conflicts in implement=
ation and solving
> > > > > > > > > > > similar problem):
> > > > > > > > > > >
> > > > > > > > > > > Previous result:
> > > > > > > > > > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
> > > > > > > > > > > Execution Results after 905 seconds
> > > > > > > > > > > -----------------------------------------------------=
-------------
> > > > > > > > > > >                   Executed        Time (=C2=B5s)     =
  Rate
> > > > > > > > > > >   STOCK_LEVEL     2542            27121571486.2   0.0=
9 txn/s
> > > > > > > > > > > -----------------------------------------------------=
-------------
> > > > > > > > > > >   TOTAL           2542            27121571486.2   0.0=
9 txn/s
> > > > > > > > > > >
> > > > > > > > > > > This patch:
> > > > > > > > > > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
> > > > > > > > > > > Execution Results after 900 seconds
> > > > > > > > > > > -----------------------------------------------------=
-------------
> > > > > > > > > > >                   Executed        Time (=C2=B5s)     =
  Rate
> > > > > > > > > > >   STOCK_LEVEL     1594            27061522574.4   0.0=
6 txn/s
> > > > > > > > > > > -----------------------------------------------------=
-------------
> > > > > > > > > > >   TOTAL           1594            27061522574.4   0.0=
6 txn/s
> > > > > > > > > > >
> > > > > > > > > > > Unpatched version is always around ~500.
> > > > > > > > > >
> > > > > > > > > > Thanks for the test results!
> > > > > > > > > >
> > > > > > > > > > > I think there are a few points here:
> > > > > > > > > > > - Refault distance make use of page shadow so it can =
better
> > > > > > > > > > > distinguish evicted pages of different access pattern=
 (re-access
> > > > > > > > > > > distance).
> > > > > > > > > > > - Throttled refault distance can help hold part of wo=
rkingset when
> > > > > > > > > > > memory is too small to hold the whole workingset.
> > > > > > > > > > >
> > > > > > > > > > > So maybe part of this patch and the bits of previous =
series can be
> > > > > > > > > > > combined to work better on this issue, how do you thi=
nk?
> > > > > > > > > >
> > > > > > > > > > I'll try to find some time this week to look at your RF=
C. It'd be a
> > > > > > > >
> > > > > > > > Hi Yu,
> > > > > > > >
> > > > > > > > I'm working on V4 of the RFC now, which just update some co=
mments, and
> > > > > > > > skip anon page re-activation in refault path for mglru whic=
h was not
> > > > > > > > very helpful, only some tiny adjustment.
> > > > > > > > And I found it easier to test with fio, using following tes=
t script:
> > > > > > > >
> > > > > > > > #!/bin/bash
> > > > > > > > swapoff -a
> > > > > > > >
> > > > > > > > modprobe brd rd_nr=3D1 rd_size=3D16777216
> > > > > > > > mkfs.ext4 /dev/ram0
> > > > > > > > mount /dev/ram0 /mnt
> > > > > > > >
> > > > > > > > mkdir -p /sys/fs/cgroup/benchmark
> > > > > > > > cd /sys/fs/cgroup/benchmark
> > > > > > > >
> > > > > > > > echo 4G > memory.max
> > > > > > > > echo $$ > cgroup.procs
> > > > > > > > echo 3 > /proc/sys/vm/drop_caches
> > > > > > > >
> > > > > > > > fio -name=3Dmglru --numjobs=3D12 --directory=3D/mnt --size=
=3D1024m \
> > > > > > > >           --buffered=3D1 --ioengine=3Dio_uring --iodepth=3D=
128 \
> > > > > > > >           --iodepth_batch_submit=3D32 --iodepth_batch_compl=
ete=3D32 \
> > > > > > > >           --rw=3Drandread --random_distribution=3Dzipf:0.5 =
--norandommap \
> > > > > > > >           --time_based --ramp_time=3D5m --runtime=3D5m --gr=
oup_reporting
> > > > > > > >
> > > > > > > > zipf:0.5 is used here to simulate a cached read with slight=
 bias
> > > > > > > > towards certain pages.
> > > > > > > > Unpatched 6.7-rc4:
> > > > > > > > Run status group 0 (all jobs):
> > > > > > > >    READ: bw=3D6548MiB/s (6866MB/s), 6548MiB/s-6548MiB/s
> > > > > > > > (6866MB/s-6866MB/s), io=3D1918GiB (2060GB), run=3D300001-30=
0001msec
> > > > > > > >
> > > > > > > > Patched with RFC v4:
> > > > > > > > Run status group 0 (all jobs):
> > > > > > > >    READ: bw=3D7270MiB/s (7623MB/s), 7270MiB/s-7270MiB/s
> > > > > > > > (7623MB/s-7623MB/s), io=3D2130GiB (2287GB), run=3D300001-30=
0001msec
> > > > > > > >
> > > > > > > > Patched with this series:
> > > > > > > > Run status group 0 (all jobs):
> > > > > > > >    READ: bw=3D7098MiB/s (7442MB/s), 7098MiB/s-7098MiB/s
> > > > > > > > (7442MB/s-7442MB/s), io=3D2079GiB (2233GB), run=3D300002-30=
0002msec
> > > > > > > >
> > > > > > > > MGLRU off:
> > > > > > > > Run status group 0 (all jobs):
> > > > > > > >    READ: bw=3D6525MiB/s (6842MB/s), 6525MiB/s-6525MiB/s
> > > > > > > > (6842MB/s-6842MB/s), io=3D1912GiB (2052GB), run=3D300002-30=
0002msec
> > > > > > > >
> > > > > > > > - If I change zipf:0.5 to random:
> > > > > > > > Unpatched 6.7-rc4:
> > > > > > > > Patched with this series:
> > > > > > > > Run status group 0 (all jobs):
> > > > > > > >    READ: bw=3D5975MiB/s (6265MB/s), 5975MiB/s-5975MiB/s
> > > > > > > > (6265MB/s-6265MB/s), io=3D1750GiB (1879GB), run=3D300002-30=
0002msec
> > > > > > > >
> > > > > > > > Patched with RFC v4:
> > > > > > > > Run status group 0 (all jobs):
> > > > > > > >    READ: bw=3D5987MiB/s (6278MB/s), 5987MiB/s-5987MiB/s
> > > > > > > > (6278MB/s-6278MB/s), io=3D1754GiB (1883GB), run=3D300001-30=
0001msec
> > > > > > > >
> > > > > > > > Patched with this series:
> > > > > > > > Run status group 0 (all jobs):
> > > > > > > >    READ: bw=3D5839MiB/s (6123MB/s), 5839MiB/s-5839MiB/s
> > > > > > > > (6123MB/s-6123MB/s), io=3D1711GiB (1837GB), run=3D300001-30=
0001msec
> > > > > > > >
> > > > > > > > MGLRU off:
> > > > > > > > Run status group 0 (all jobs):
> > > > > > > >    READ: bw=3D5689MiB/s (5965MB/s), 5689MiB/s-5689MiB/s
> > > > > > > > (5965MB/s-5965MB/s), io=3D1667GiB (1790GB), run=3D300003-30=
0003msec
> > > > > > > >
> > > > > > > > fio uses ramdisk so LRU accuracy will have smaller impact. =
The Mongodb
> > > > > > > > test I provided before uses a SATA SSD so it will have a mu=
ch higher
> > > > > > > > impact. I'll provides a script to setup the test case and r=
un it, it's
> > > > > > > > more complex to setup than fio since involving setting up m=
ultiple
> > > > > > > > replicas and auth and hundreds of GB of test fixtures, I'm =
currently
> > > > > > > > occupied by some other tasks but will try best to send them=
 out as
> > > > > > > > soon as possible.
> > > > > > >
> > > > > > > Thanks! Apparently your RFC did show better IOPS with both ac=
cess
> > > > > > > patterns, which was a surprise to me because it had higher re=
faults
> > > > > > > and usually higher refautls result in worse performance.
> > >
> > > And thanks for providing the refaults I requested for -- your data
> > > below confirms what I mentioned above:
> > >
> > > For fio:
> > >                            Your RFC   This series   Change
> > >   workingset_refault_file  628192729  596790506     -5%
> > >   IOPS                     1862k      1830k         -2%
> > >
> > > For MongoDB:
> > >                            Your RFC   This series   Change
> > >   workingset_refault_anon  10512      35277         +30%
> > >   workingset_refault_file  22751782   20335355      -11%
> > >   total                    22762294   20370632      -11%
> > >   TPS                      0.09       0.06          -33%
> > >
> > > For MongoDB, this series should be a big win (but apparently it's not=
),
> > > especially when using zram, since an anon refault should be a lot
> > > cheaper than a file refault.
> > >
> > > So, I'm baffled...
> > >
> > > One important detail I forgot to mention: based on your data from
> > > lru_gen_full, I think there is another difference between our Kconfig=
s:
> > >
> > >                   Your Kconfig  My Kconfig  Max possible
> > >   LRU_REFS_WIDTH  1             2           2
> >
> > Hi Yu,
> >
> > Thanks for the info, my fault, I forgot to update my config as I was
> > testing some other features.
> > Buf after I changed LRU_REFS_WIDTH to 2 by disabling IDLE_PAGE, thing
> > got much worse for MongoDB test:
> >
> > With LRU_REFS_WIDTH =3D=3D 2:
> >
> > This patch:
> > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
> > Execution Results after 919 seconds
> > ------------------------------------------------------------------
> >                   Executed        Time (=C2=B5s)       Rate
> >   STOCK_LEVEL     488             27598136201.9   0.02 txn/s
> > ------------------------------------------------------------------
> >   TOTAL           488             27598136201.9   0.02 txn/s
> >
> > memcg    86 /system.slice/docker-1c3a90be9f0a072f5719332419550cd0e1455f=
2cd5863bc2780ca4d3f913ece5.scope
> >  node     0
> >           1     948187          0x          0x
> >                      0          0           0           0           0
> >          0           0=C2=B7
> >                      1          0           0           0           0
> >          0           0=C2=B7
> >                      2          0           0           0           0
> >          0           0=C2=B7
> >                      3          0           0           0           0
> >          0           0=C2=B7
> >                                 0           0           0           0
> >          0           0=C2=B7
> >           2     948187          0     6051788=C2=B7
> >                      0          0r          0e          0p      11916r
> >      66442e          0p
> >                      1          0r          0e          0p        903r
> >      16888e          0p
> >                      2          0r          0e          0p        459r
> >       9764e          0p
> >                      3          0r          0e          0p          0r
> >          0e       2874p
> >                                 0           0           0           0
> >          0           0=C2=B7
> >           3     948187    1353160        6351=C2=B7
> >                      0          0           0           0           0
> >          0           0=C2=B7
> >                      1          0           0           0           0
> >          0           0=C2=B7
> >                      2          0           0           0           0
> >          0           0=C2=B7
> >                      3          0           0           0           0
> >          0           0=C2=B7
> >                                 0           0           0           0
> >          0           0=C2=B7
> >           4      73045      23573          12=C2=B7
> >                      0          0R          0T          0     3498607R
> >    4868605T          0=C2=B7
> >                      1          0R          0T          0     3012246R
> >    3270261T          0=C2=B7
> >                      2          0R          0T          0     2498608R
> >    2839104T          0=C2=B7
> >                      3          0R          0T          0           0R
> >    1983947T          0=C2=B7
> >                           1486579L          0O    1380614Y       2945N
> >       2945F       2734A
> >
> > workingset_refault_anon 0
> > workingset_refault_file 18130598
> >
> >               total        used        free      shared  buff/cache   a=
vailable
> > Mem:          31978        6705         312          20       24960    =
   24786
> > Swap:         31977           4       31973
> >
> > RFC:
> > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
> > Execution Results after 908 seconds
> > ------------------------------------------------------------------
> >                   Executed        Time (=C2=B5s)       Rate
> >   STOCK_LEVEL     2252            27159962888.2   0.08 txn/s
> > ------------------------------------------------------------------
> >   TOTAL           2252            27159962888.2   0.08 txn/s
> >
> > workingset_refault_anon 22585
> > workingset_refault_file 22715256
> >
> > memcg    66 /system.slice/docker-0989446ff78106e32d3f400a0cf371c9a70328=
1bded86d6d6bb1af706ebb25da.scope
> >  node     0
> >          22     563007       2274     1198225=C2=B7
> >                      0          0r          1e          0p          0r
> >     697076e          0p
> >                      1          0r          0e          0p          0r
> >          0e     325661p
> >                      2          0r          0e          0p          0r
> >          0e     888728p
> >                      3          0r          0e          0p          0r
> >          0e    3602238p
> >                                 0           0           0           0
> >          0           0=C2=B7
> >          23     532222       7525     4948747=C2=B7
> >                      0          0           0           0           0
> >          0           0=C2=B7
> >                      1          0           0           0           0
> >          0           0=C2=B7
> >                      2          0           0           0           0
> >          0           0=C2=B7
> >                      3          0           0           0           0
> >          0           0=C2=B7
> >                                 0           0           0           0
> >          0           0=C2=B7
> >          24     500367    1214667        3292=C2=B7
> >                      0          0           0           0           0
> >          0           0=C2=B7
> >                      1          0           0           0           0
> >          0           0=C2=B7
> >                      2          0           0           0           0
> >          0           0=C2=B7
> >                      3          0           0           0           0
> >          0           0=C2=B7
> >                                 0           0           0           0
> >          0           0=C2=B7
> >          25     469692      40797         466=C2=B7
> >                      0          0R        271T          0           0R
> >    1162165T          0=C2=B7
> >                      1          0R          0T          0      774028R
> >    1205332T          0=C2=B7
> >                      2          0R          0T          0           0R
> >     932484T          0=C2=B7
> >                      3          0R          1T          0           0R
> >    4252158T          0=C2=B7
> >                          25178380L     156515O   23953602Y      59234N
> >      49391F      48664A
> >
> >               total        used        free      shared  buff/cache   a=
vailable
> > Mem:          31978        6968         338           5       24671    =
   24555
> > Swap:         31977        1533       30444
> >
> > Using same mongodb config (a 3 replica cluster using the same config):
> > {
> >     "net": {
> >         "bindIpAll": true,
> >         "ipv6": false,
> >         "maxIncomingConnections": 10000,
> >     },
> >     "setParameter": {
> >         "disabledSecureAllocatorDomains": "*"
> >     },
> >     "replication": {
> >         "oplogSizeMB": 10480,
> >         "replSetName": "issa-tpcc_0"
> >     },
> >     "security": {
> >         "keyFile": "/data/db/keyfile"
> >     },
> >     "storage": {
> >         "dbPath": "/data/db/",
> >         "syncPeriodSecs": 60,
> >         "directoryPerDB": true,
> >         "wiredTiger": {
> >             "engineConfig": {
> >                 "cacheSizeGB": 5
> >             }
> >         }
> >     },
> >     "systemLog": {
> >         "destination": "file",
> >         "logAppend": true,
> >         "logRotate": "rename",
> >         "path": "/data/db/mongod.log",
> >         "verbosity": 0
> >     }
> > }
> >
> > The test environment have 32g memory and 16 core.
> >
> > Per my analyze, the access pattern for the mongodb test is that page
> > will be re-access long after it's evicted so PID controller won't
> > protect higher tier. That RFC will make use of the long existing
> > shadow to do feedback to PID/Gen so the result will be much better.
> > Still need more adjusting though, will try to do a rebase on top of
> > mm-unstable which includes your patch.
> >
> > I've no idea why the workingset_refault_* is higher in the better
> > case, this a clearly an IO bound workload, Memory and IO is busy while
> > CPU is not full...
> >
> > I've uploaded my local reproducer here:
> > https://github.com/ryncsn/emm-test-project/tree/master/mongo-cluster
> > https://github.com/ryncsn/py-tpcc
>
> Thanks for the repos -- I'm trying them right now. Which MongoDB
> version did you use? setup.sh didn't seem to install it.
>
> Also do you have a QEMU image? It'd be a lot easier for me to
> duplicate the exact environment by looking into it.

I ended up using docker.io/mongodb/mongodb-community-server:latest,
and it's not working:

# docker exec -it mongo-r1 mongosh --eval \
'"rs.initiate({
    _id: "issa-tpcc_0",
    members: [
      {_id: 0, host: "mongo-r1"},
      {_id: 1, host: "mongo-r2"},
      {_id: 2, host: "mongo-r3"}
    ]
})"'
Emulate Docker CLI using podman. Create /etc/containers/nodocker to quiet m=
sg.
Error: can only create exec sessions on running containers: container
state improper