[Request]: Improve filesystem performance #882

Closed
Feature
Closed
[Request]: Improve filesystem performance#882
Feature
Assignees
jglogan

Description

@vsarunas
vsarunas
opened on Nov 17, 2025

Feature or enhancement request details

While trying to find a way to reproduce #614 noticed that filesystem performance is ~3 times slower compared to a Qemu VM.

For example create a large container:

container run --cpus 8 --memory 16G -ti ubuntu:latest /bin/bash

Can run a simple test:

apt-get update; apt-get install -y curl fio
curl -sL https://yabs.sh -i | bash -s -- -i -n -g

M1 Max:

io Disk Speed Tests (Mixed R/W 50/50) (Partition /dev/vdb):
---------------------------------
Block Size | 4k (IOPS) | 64k (IOPS)
------ | --- ---- | ---- ----
Read | 112.95 MB/s (28.2k) | 328.21 MB/s (5.1k)
Write | 112.88 MB/s (28.2k) | 337.97 MB/s (5.2k)
Total | 225.84 MB/s (56.4k) | 666.18 MB/s (10.4k)
| |
Block Size | 512k (IOPS) | 1m (IOPS)
------ | --- ---- | ---- ----
Read | 256.00 MB/s (500) | 432.09 MB/s (421)
Write | 277.89 MB/s (542) | 482.09 MB/s (470)
Total | 533.89 MB/s (1.0k) | 914.18 MB/s (891)
YABS completed in 14 sec

Multipass VM with Ubuntu with ext4:

fio Disk Speed Tests (Mixed R/W 50/50) (Partition /dev/sda1):
---------------------------------
Block Size | 4k (IOPS) | 64k (IOPS)
------ | --- ---- | ---- ----
Read | 134.06 MB/s (33.5k) | 1.75 GB/s (27.3k)
Write | 133.97 MB/s (33.4k) | 1.80 GB/s (28.1k)
Total | 268.04 MB/s (67.0k) | 3.55 GB/s (55.5k)
| |
Block Size | 512k (IOPS) | 1m (IOPS)
------ | --- ---- | ---- ----
Read | 4.74 GB/s (9.2k) | 6.52 GB/s (6.3k)
Write | 5.14 GB/s (10.0k) | 7.27 GB/s (7.1k)
Total | 9.89 GB/s (19.3k) | 13.79 GB/s (13.4k)

Docker:

fio Disk Speed Tests (Mixed R/W 50/50) (Partition overlay):
---------------------------------
Block Size | 4k (IOPS) | 64k (IOPS)
------ | --- ---- | ---- ----
Read | 416.23 MB/s (104.0k) | 5.32 GB/s (83.2k)
Write | 415.96 MB/s (103.9k) | 5.48 GB/s (85.6k)
Total | 832.20 MB/s (208.0k) | 10.81 GB/s (168.9k)
| |
Block Size | 512k (IOPS) | 1m (IOPS)
------ | --- ---- | ---- ----
Read | 11.97 GB/s (23.3k) | 14.16 GB/s (13.8k)
Write | 12.99 GB/s (25.3k) | 15.79 GB/s (15.4k)
Total | 24.96 GB/s (48.7k) | 29.95 GB/s (29.2k)

The test are shorter; but representative; longer duration for example with container it can run with close 1000MiB/s, and occasional drops to 300MiBs. Native block performance is ~3000MB/s.

Long duration test can be launched via:

fio --name=rand_rw_512k --ioengine=libaio --rw=randrw --rwmixread=50 --bs=512k --iodepth=64 --numjobs=2 --size=10G --runtime=3600 --time_based --gtod_reduce=1 --direct=1 --filename=./test.fio --group_reporting

Instruments only has shown pwritev calls for the most part from an IO thread:

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    Skip to content
    [Request]: Improve filesystem performance #882
    Closed
    Feature
    Closed
    [Request]: Improve filesystem performance#882
    Feature
    Assignees
    jglogan
    Description
    @vsarunas
    vsarunas
    opened on Nov 17, 2025
    Feature or enhancement request details
    While trying to find a way to reproduce #614 noticed that filesystem performance is ~3 times slower compared to a Qemu VM.
    For example create a large container:
    container run --cpus 8 --memory 16G -ti ubuntu:latest /bin/bash

    Can run a simple test:
    apt-get update; apt-get install -y curl fio
curl -sL https://yabs.sh -i | bash -s -- -i -n -g

    M1 Max:
    io Disk Speed Tests (Mixed R/W 50/50) (Partition /dev/vdb):
---------------------------------
Block Size | 4k (IOPS) | 64k (IOPS)
------ | --- ---- | ---- ----
Read | 112.95 MB/s (28.2k) | 328.21 MB/s (5.1k)
Write | 112.88 MB/s (28.2k) | 337.97 MB/s (5.2k)
Total | 225.84 MB/s (56.4k) | 666.18 MB/s (10.4k)
| |
Block Size | 512k (IOPS) | 1m (IOPS)
------ | --- ---- | ---- ----
Read | 256.00 MB/s (500) | 432.09 MB/s (421)
Write | 277.89 MB/s (542) | 482.09 MB/s (470)
Total | 533.89 MB/s (1.0k) | 914.18 MB/s (891)
YABS completed in 14 sec

    Multipass VM with Ubuntu with ext4:
    fio Disk Speed Tests (Mixed R/W 50/50) (Partition /dev/sda1):
---------------------------------
Block Size | 4k (IOPS) | 64k (IOPS)
------ | --- ---- | ---- ----
Read | 134.06 MB/s (33.5k) | 1.75 GB/s (27.3k)
Write | 133.97 MB/s (33.4k) | 1.80 GB/s (28.1k)
Total | 268.04 MB/s (67.0k) | 3.55 GB/s (55.5k)
| |
Block Size | 512k (IOPS) | 1m (IOPS)
------ | --- ---- | ---- ----
Read | 4.74 GB/s (9.2k) | 6.52 GB/s (6.3k)
Write | 5.14 GB/s (10.0k) | 7.27 GB/s (7.1k)
Total | 9.89 GB/s (19.3k) | 13.79 GB/s (13.4k)

    Docker:
    fio Disk Speed Tests (Mixed R/W 50/50) (Partition overlay):
---------------------------------
Block Size | 4k (IOPS) | 64k (IOPS)
------ | --- ---- | ---- ----
Read | 416.23 MB/s (104.0k) | 5.32 GB/s (83.2k)
Write | 415.96 MB/s (103.9k) | 5.48 GB/s (85.6k)
Total | 832.20 MB/s (208.0k) | 10.81 GB/s (168.9k)
| |
Block Size | 512k (IOPS) | 1m (IOPS)
------ | --- ---- | ---- ----
Read | 11.97 GB/s (23.3k) | 14.16 GB/s (13.8k)
Write | 12.99 GB/s (25.3k) | 15.79 GB/s (15.4k)
Total | 24.96 GB/s (48.7k) | 29.95 GB/s (29.2k)

    The test are shorter; but representative; longer duration for example with container it can run with close 1000MiB/s, and occasional drops to 300MiBs. Native block performance is ~3000MB/s.
    Long duration test can be launched via:
    fio --name=rand_rw_512k --ioengine=libaio --rw=randrw --rwmixread=50 --bs=512k --iodepth=64 --numjobs=2 --size=10G --runtime=3600 --time_based --gtod_reduce=1 --direct=1 --filename=./test.fio --group_reporting

    Instruments only has shown pwritev calls for the most part from an IO thread:
    Image
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      Skip to content
      [Request]: Improve filesystem performance #882
      Closed
      Feature
      Closed
      [Request]: Improve filesystem performance#882
      Feature
      Assignees
      jglogan
      Description
      @vsarunas
      vsarunas
      opened on Nov 17, 2025
      Feature or enhancement request details
      While trying to find a way to reproduce #614 noticed that filesystem performance is ~3 times slower compared to a Qemu VM.
      For example create a large container:
      container run --cpus 8 --memory 16G -ti ubuntu:latest /bin/bash

      Can run a simple test:
      apt-get update; apt-get install -y curl fio
curl -sL https://yabs.sh -i | bash -s -- -i -n -g

      M1 Max:
      io Disk Speed Tests (Mixed R/W 50/50) (Partition /dev/vdb):
---------------------------------
Block Size | 4k (IOPS) | 64k (IOPS)
------ | --- ---- | ---- ----
Read | 112.95 MB/s (28.2k) | 328.21 MB/s (5.1k)
Write | 112.88 MB/s (28.2k) | 337.97 MB/s (5.2k)
Total | 225.84 MB/s (56.4k) | 666.18 MB/s (10.4k)
| |
Block Size | 512k (IOPS) | 1m (IOPS)
------ | --- ---- | ---- ----
Read | 256.00 MB/s (500) | 432.09 MB/s (421)
Write | 277.89 MB/s (542) | 482.09 MB/s (470)
Total | 533.89 MB/s (1.0k) | 914.18 MB/s (891)
YABS completed in 14 sec

      Multipass VM with Ubuntu with ext4:
      fio Disk Speed Tests (Mixed R/W 50/50) (Partition /dev/sda1):
---------------------------------
Block Size | 4k (IOPS) | 64k (IOPS)
------ | --- ---- | ---- ----
Read | 134.06 MB/s (33.5k) | 1.75 GB/s (27.3k)
Write | 133.97 MB/s (33.4k) | 1.80 GB/s (28.1k)
Total | 268.04 MB/s (67.0k) | 3.55 GB/s (55.5k)
| |
Block Size | 512k (IOPS) | 1m (IOPS)
------ | --- ---- | ---- ----
Read | 4.74 GB/s (9.2k) | 6.52 GB/s (6.3k)
Write | 5.14 GB/s (10.0k) | 7.27 GB/s (7.1k)
Total | 9.89 GB/s (19.3k) | 13.79 GB/s (13.4k)

      Docker:
      fio Disk Speed Tests (Mixed R/W 50/50) (Partition overlay):
---------------------------------
Block Size | 4k (IOPS) | 64k (IOPS)
------ | --- ---- | ---- ----
Read | 416.23 MB/s (104.0k) | 5.32 GB/s (83.2k)
Write | 415.96 MB/s (103.9k) | 5.48 GB/s (85.6k)
Total | 832.20 MB/s (208.0k) | 10.81 GB/s (168.9k)
| |
Block Size | 512k (IOPS) | 1m (IOPS)
------ | --- ---- | ---- ----
Read | 11.97 GB/s (23.3k) | 14.16 GB/s (13.8k)
Write | 12.99 GB/s (25.3k) | 15.79 GB/s (15.4k)
Total | 24.96 GB/s (48.7k) | 29.95 GB/s (29.2k)

      The test are shorter; but representative; longer duration for example with container it can run with close 1000MiB/s, and occasional drops to 300MiBs. Native block performance is ~3000MB/s.
      Long duration test can be launched via:
      fio --name=rand_rw_512k --ioengine=libaio --rw=randrw --rwmixread=50 --bs=512k --iodepth=64 --numjobs=2 --size=10G --runtime=3600 --time_based --gtod_reduce=1 --direct=1 --filename=./test.fio --group_reporting

      Instruments only has shown pwritev calls for the most part from an IO thread:
      Image
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(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

        Skip to content
        [Request]: Improve filesystem performance #882
        Closed
        Feature
        Closed
        [Request]: Improve filesystem performance#882
        Feature
        Assignees
        jglogan
        Description
        @vsarunas
        vsarunas
        opened on Nov 17, 2025
        Feature or enhancement request details
        While trying to find a way to reproduce #614 noticed that filesystem performance is ~3 times slower compared to a Qemu VM.
        For example create a large container:
        container run --cpus 8 --memory 16G -ti ubuntu:latest /bin/bash

        Can run a simple test:
        apt-get update; apt-get install -y curl fio
curl -sL https://yabs.sh -i | bash -s -- -i -n -g

        M1 Max:
        io Disk Speed Tests (Mixed R/W 50/50) (Partition /dev/vdb):
---------------------------------
Block Size | 4k (IOPS) | 64k (IOPS)
------ | --- ---- | ---- ----
Read | 112.95 MB/s (28.2k) | 328.21 MB/s (5.1k)
Write | 112.88 MB/s (28.2k) | 337.97 MB/s (5.2k)
Total | 225.84 MB/s (56.4k) | 666.18 MB/s (10.4k)
| |
Block Size | 512k (IOPS) | 1m (IOPS)
------ | --- ---- | ---- ----
Read | 256.00 MB/s (500) | 432.09 MB/s (421)
Write | 277.89 MB/s (542) | 482.09 MB/s (470)
Total | 533.89 MB/s (1.0k) | 914.18 MB/s (891)
YABS completed in 14 sec

        Multipass VM with Ubuntu with ext4:
        fio Disk Speed Tests (Mixed R/W 50/50) (Partition /dev/sda1):
---------------------------------
Block Size | 4k (IOPS) | 64k (IOPS)
------ | --- ---- | ---- ----
Read | 134.06 MB/s (33.5k) | 1.75 GB/s (27.3k)
Write | 133.97 MB/s (33.4k) | 1.80 GB/s (28.1k)
Total | 268.04 MB/s (67.0k) | 3.55 GB/s (55.5k)
| |
Block Size | 512k (IOPS) | 1m (IOPS)
------ | --- ---- | ---- ----
Read | 4.74 GB/s (9.2k) | 6.52 GB/s (6.3k)
Write | 5.14 GB/s (10.0k) | 7.27 GB/s (7.1k)
Total | 9.89 GB/s (19.3k) | 13.79 GB/s (13.4k)

        Docker:
        fio Disk Speed Tests (Mixed R/W 50/50) (Partition overlay):
---------------------------------
Block Size | 4k (IOPS) | 64k (IOPS)
------ | --- ---- | ---- ----
Read | 416.23 MB/s (104.0k) | 5.32 GB/s (83.2k)
Write | 415.96 MB/s (103.9k) | 5.48 GB/s (85.6k)
Total | 832.20 MB/s (208.0k) | 10.81 GB/s (168.9k)
| |
Block Size | 512k (IOPS) | 1m (IOPS)
------ | --- ---- | ---- ----
Read | 11.97 GB/s (23.3k) | 14.16 GB/s (13.8k)
Write | 12.99 GB/s (25.3k) | 15.79 GB/s (15.4k)
Total | 24.96 GB/s (48.7k) | 29.95 GB/s (29.2k)

        The test are shorter; but representative; longer duration for example with container it can run with close 1000MiB/s, and occasional drops to 300MiBs. Native block performance is ~3000MB/s.
        Long duration test can be launched via:
        fio --name=rand_rw_512k --ioengine=libaio --rw=randrw --rwmixread=50 --bs=512k --iodepth=64 --numjobs=2 --size=10G --runtime=3600 --time_based --gtod_reduce=1 --direct=1 --filename=./test.fio --group_reporting

        Instruments only has shown pwritev calls for the most part from an IO thread:
        Image
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var __m = "youtube.com";
var __re = new RegExp('^' + "youtube\\.com" + '

          Skip to content
          [Request]: Improve filesystem performance #882
          Closed
          Feature
          Closed
          [Request]: Improve filesystem performance#882
          Feature
          Assignees
          jglogan
          Description
          @vsarunas
          vsarunas
          opened on Nov 17, 2025
          Feature or enhancement request details
          While trying to find a way to reproduce #614 noticed that filesystem performance is ~3 times slower compared to a Qemu VM.
          For example create a large container:
          container run --cpus 8 --memory 16G -ti ubuntu:latest /bin/bash

          Can run a simple test:
          apt-get update; apt-get install -y curl fio
curl -sL https://yabs.sh -i | bash -s -- -i -n -g

          M1 Max:
          io Disk Speed Tests (Mixed R/W 50/50) (Partition /dev/vdb):
---------------------------------
Block Size | 4k (IOPS) | 64k (IOPS)
------ | --- ---- | ---- ----
Read | 112.95 MB/s (28.2k) | 328.21 MB/s (5.1k)
Write | 112.88 MB/s (28.2k) | 337.97 MB/s (5.2k)
Total | 225.84 MB/s (56.4k) | 666.18 MB/s (10.4k)
| |
Block Size | 512k (IOPS) | 1m (IOPS)
------ | --- ---- | ---- ----
Read | 256.00 MB/s (500) | 432.09 MB/s (421)
Write | 277.89 MB/s (542) | 482.09 MB/s (470)
Total | 533.89 MB/s (1.0k) | 914.18 MB/s (891)
YABS completed in 14 sec

          Multipass VM with Ubuntu with ext4:
          fio Disk Speed Tests (Mixed R/W 50/50) (Partition /dev/sda1):
---------------------------------
Block Size | 4k (IOPS) | 64k (IOPS)
------ | --- ---- | ---- ----
Read | 134.06 MB/s (33.5k) | 1.75 GB/s (27.3k)
Write | 133.97 MB/s (33.4k) | 1.80 GB/s (28.1k)
Total | 268.04 MB/s (67.0k) | 3.55 GB/s (55.5k)
| |
Block Size | 512k (IOPS) | 1m (IOPS)
------ | --- ---- | ---- ----
Read | 4.74 GB/s (9.2k) | 6.52 GB/s (6.3k)
Write | 5.14 GB/s (10.0k) | 7.27 GB/s (7.1k)
Total | 9.89 GB/s (19.3k) | 13.79 GB/s (13.4k)

          Docker:
          fio Disk Speed Tests (Mixed R/W 50/50) (Partition overlay):
---------------------------------
Block Size | 4k (IOPS) | 64k (IOPS)
------ | --- ---- | ---- ----
Read | 416.23 MB/s (104.0k) | 5.32 GB/s (83.2k)
Write | 415.96 MB/s (103.9k) | 5.48 GB/s (85.6k)
Total | 832.20 MB/s (208.0k) | 10.81 GB/s (168.9k)
| |
Block Size | 512k (IOPS) | 1m (IOPS)
------ | --- ---- | ---- ----
Read | 11.97 GB/s (23.3k) | 14.16 GB/s (13.8k)
Write | 12.99 GB/s (25.3k) | 15.79 GB/s (15.4k)
Total | 24.96 GB/s (48.7k) | 29.95 GB/s (29.2k)

          The test are shorter; but representative; longer duration for example with container it can run with close 1000MiB/s, and occasional drops to 300MiBs. Native block performance is ~3000MB/s.
          Long duration test can be launched via:
          fio --name=rand_rw_512k --ioengine=libaio --rw=randrw --rwmixread=50 --bs=512k --iodepth=64 --numjobs=2 --size=10G --runtime=3600 --time_based --gtod_reduce=1 --direct=1 --filename=./test.fio --group_reporting

          Instruments only has shown pwritev calls for the most part from an IO thread:
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            Skip to content
            [Request]: Improve filesystem performance #882
            Closed
            Feature
            Closed
            [Request]: Improve filesystem performance#882
            Feature
            Assignees
            jglogan
            Description
            @vsarunas
            vsarunas
            opened on Nov 17, 2025
            Feature or enhancement request details
            While trying to find a way to reproduce #614 noticed that filesystem performance is ~3 times slower compared to a Qemu VM.
            For example create a large container:
            container run --cpus 8 --memory 16G -ti ubuntu:latest /bin/bash

            Can run a simple test:
            apt-get update; apt-get install -y curl fio
curl -sL https://yabs.sh -i | bash -s -- -i -n -g

            M1 Max:
            io Disk Speed Tests (Mixed R/W 50/50) (Partition /dev/vdb):
---------------------------------
Block Size | 4k (IOPS) | 64k (IOPS)
------ | --- ---- | ---- ----
Read | 112.95 MB/s (28.2k) | 328.21 MB/s (5.1k)
Write | 112.88 MB/s (28.2k) | 337.97 MB/s (5.2k)
Total | 225.84 MB/s (56.4k) | 666.18 MB/s (10.4k)
| |
Block Size | 512k (IOPS) | 1m (IOPS)
------ | --- ---- | ---- ----
Read | 256.00 MB/s (500) | 432.09 MB/s (421)
Write | 277.89 MB/s (542) | 482.09 MB/s (470)
Total | 533.89 MB/s (1.0k) | 914.18 MB/s (891)
YABS completed in 14 sec

            Multipass VM with Ubuntu with ext4:
            fio Disk Speed Tests (Mixed R/W 50/50) (Partition /dev/sda1):
---------------------------------
Block Size | 4k (IOPS) | 64k (IOPS)
------ | --- ---- | ---- ----
Read | 134.06 MB/s (33.5k) | 1.75 GB/s (27.3k)
Write | 133.97 MB/s (33.4k) | 1.80 GB/s (28.1k)
Total | 268.04 MB/s (67.0k) | 3.55 GB/s (55.5k)
| |
Block Size | 512k (IOPS) | 1m (IOPS)
------ | --- ---- | ---- ----
Read | 4.74 GB/s (9.2k) | 6.52 GB/s (6.3k)
Write | 5.14 GB/s (10.0k) | 7.27 GB/s (7.1k)
Total | 9.89 GB/s (19.3k) | 13.79 GB/s (13.4k)

            Docker:
            fio Disk Speed Tests (Mixed R/W 50/50) (Partition overlay):
---------------------------------
Block Size | 4k (IOPS) | 64k (IOPS)
------ | --- ---- | ---- ----
Read | 416.23 MB/s (104.0k) | 5.32 GB/s (83.2k)
Write | 415.96 MB/s (103.9k) | 5.48 GB/s (85.6k)
Total | 832.20 MB/s (208.0k) | 10.81 GB/s (168.9k)
| |
Block Size | 512k (IOPS) | 1m (IOPS)
------ | --- ---- | ---- ----
Read | 11.97 GB/s (23.3k) | 14.16 GB/s (13.8k)
Write | 12.99 GB/s (25.3k) | 15.79 GB/s (15.4k)
Total | 24.96 GB/s (48.7k) | 29.95 GB/s (29.2k)

            The test are shorter; but representative; longer duration for example with container it can run with close 1000MiB/s, and occasional drops to 300MiBs. Native block performance is ~3000MB/s.
            Long duration test can be launched via:
            fio --name=rand_rw_512k --ioengine=libaio --rw=randrw --rwmixread=50 --bs=512k --iodepth=64 --numjobs=2 --size=10G --runtime=3600 --time_based --gtod_reduce=1 --direct=1 --filename=./test.fio --group_reporting

            Instruments only has shown pwritev calls for the most part from an IO thread:
            Image
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, 'i');
if (__m === '*' || __re.test(location.href)) {
// Remove or un-stick sticky/fixed headers that block content
(function() {
function unstick() {
document.querySelectorAll('header, nav, [role="banner"], .header, .navbar, .sticky, .fixed-top, [style*="position: fixed"], [style*="position:sticky"]').forEach(function(el) {
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try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

              Skip to content
              [Request]: Improve filesystem performance #882
              Closed
              Feature
              Closed
              [Request]: Improve filesystem performance#882
              Feature
              Assignees
              jglogan
              Description
              @vsarunas
              vsarunas
              opened on Nov 17, 2025
              Feature or enhancement request details
              While trying to find a way to reproduce #614 noticed that filesystem performance is ~3 times slower compared to a Qemu VM.
              For example create a large container:
              container run --cpus 8 --memory 16G -ti ubuntu:latest /bin/bash

              Can run a simple test:
              apt-get update; apt-get install -y curl fio
curl -sL https://yabs.sh -i | bash -s -- -i -n -g

              M1 Max:
              io Disk Speed Tests (Mixed R/W 50/50) (Partition /dev/vdb):
---------------------------------
Block Size | 4k (IOPS) | 64k (IOPS)
------ | --- ---- | ---- ----
Read | 112.95 MB/s (28.2k) | 328.21 MB/s (5.1k)
Write | 112.88 MB/s (28.2k) | 337.97 MB/s (5.2k)
Total | 225.84 MB/s (56.4k) | 666.18 MB/s (10.4k)
| |
Block Size | 512k (IOPS) | 1m (IOPS)
------ | --- ---- | ---- ----
Read | 256.00 MB/s (500) | 432.09 MB/s (421)
Write | 277.89 MB/s (542) | 482.09 MB/s (470)
Total | 533.89 MB/s (1.0k) | 914.18 MB/s (891)
YABS completed in 14 sec

              Multipass VM with Ubuntu with ext4:
              fio Disk Speed Tests (Mixed R/W 50/50) (Partition /dev/sda1):
---------------------------------
Block Size | 4k (IOPS) | 64k (IOPS)
------ | --- ---- | ---- ----
Read | 134.06 MB/s (33.5k) | 1.75 GB/s (27.3k)
Write | 133.97 MB/s (33.4k) | 1.80 GB/s (28.1k)
Total | 268.04 MB/s (67.0k) | 3.55 GB/s (55.5k)
| |
Block Size | 512k (IOPS) | 1m (IOPS)
------ | --- ---- | ---- ----
Read | 4.74 GB/s (9.2k) | 6.52 GB/s (6.3k)
Write | 5.14 GB/s (10.0k) | 7.27 GB/s (7.1k)
Total | 9.89 GB/s (19.3k) | 13.79 GB/s (13.4k)

              Docker:
              fio Disk Speed Tests (Mixed R/W 50/50) (Partition overlay):
---------------------------------
Block Size | 4k (IOPS) | 64k (IOPS)
------ | --- ---- | ---- ----
Read | 416.23 MB/s (104.0k) | 5.32 GB/s (83.2k)
Write | 415.96 MB/s (103.9k) | 5.48 GB/s (85.6k)
Total | 832.20 MB/s (208.0k) | 10.81 GB/s (168.9k)
| |
Block Size | 512k (IOPS) | 1m (IOPS)
------ | --- ---- | ---- ----
Read | 11.97 GB/s (23.3k) | 14.16 GB/s (13.8k)
Write | 12.99 GB/s (25.3k) | 15.79 GB/s (15.4k)
Total | 24.96 GB/s (48.7k) | 29.95 GB/s (29.2k)

              The test are shorter; but representative; longer duration for example with container it can run with close 1000MiB/s, and occasional drops to 300MiBs. Native block performance is ~3000MB/s.
              Long duration test can be launched via:
              fio --name=rand_rw_512k --ioengine=libaio --rw=randrw --rwmixread=50 --bs=512k --iodepth=64 --numjobs=2 --size=10G --runtime=3600 --time_based --gtod_reduce=1 --direct=1 --filename=./test.fio --group_reporting

              Instruments only has shown pwritev calls for the most part from an IO thread:
              Image
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, 'i');
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// Universal Dark Mode - works on any site
(function() {
var enabled = true;
function applyDarkMode() {
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style.id = 'universal-dark-mode-style';
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style.textContent = '
/* Invert everything except media */
html {
filter: invert(1) hue-rotate(180deg) !important;
background: #1a1a2e !important;
}
/* Restore images, videos, iframes, canvas */
img, video, iframe, canvas, svg, picture, [style*="background-image"] {
filter: invert(1) hue-rotate(180deg) !important;
}
/* Preserve specific elements that should not be inverted */
.no-dark-mode, .no-dark-mode *,
[data-theme="light"], [data-theme="light"],
.ace_editor, .ace_editor *,
.CodeMirror, .CodeMirror *,
.monaco-editor, .monaco-editor *,
.markdown-body pre, .markdown-body pre *,
.highlight, .highlight *,
pre code, pre code * {
filter: none !important;
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/* Fix common UI elements */
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filter: invert(1) hue-rotate(180deg) !important;
background: #2d2d44 !important;
border-color: #444 !important;
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::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }
';
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var style = document.getElementById('universal-dark-mode-style');
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console.log('[Universal Dark Mode] Disabled');
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if (enabled && !document.getElementById('universal-dark-mode-style')) {
applyDarkMode();
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console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');
})();
}
} catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); }
})();
})();

                Skip to content
                [Request]: Improve filesystem performance #882
                Closed
                Feature
                Closed
                [Request]: Improve filesystem performance#882
                Feature
                Assignees
                jglogan
                Description
                @vsarunas
                vsarunas
                opened on Nov 17, 2025
                Feature or enhancement request details
                While trying to find a way to reproduce #614 noticed that filesystem performance is ~3 times slower compared to a Qemu VM.
                For example create a large container:
                container run --cpus 8 --memory 16G -ti ubuntu:latest /bin/bash

                Can run a simple test:
                apt-get update; apt-get install -y curl fio
curl -sL https://yabs.sh -i | bash -s -- -i -n -g

                M1 Max:
                io Disk Speed Tests (Mixed R/W 50/50) (Partition /dev/vdb):
---------------------------------
Block Size | 4k (IOPS) | 64k (IOPS)
------ | --- ---- | ---- ----
Read | 112.95 MB/s (28.2k) | 328.21 MB/s (5.1k)
Write | 112.88 MB/s (28.2k) | 337.97 MB/s (5.2k)
Total | 225.84 MB/s (56.4k) | 666.18 MB/s (10.4k)
| |
Block Size | 512k (IOPS) | 1m (IOPS)
------ | --- ---- | ---- ----
Read | 256.00 MB/s (500) | 432.09 MB/s (421)
Write | 277.89 MB/s (542) | 482.09 MB/s (470)
Total | 533.89 MB/s (1.0k) | 914.18 MB/s (891)
YABS completed in 14 sec

                Multipass VM with Ubuntu with ext4:
                fio Disk Speed Tests (Mixed R/W 50/50) (Partition /dev/sda1):
---------------------------------
Block Size | 4k (IOPS) | 64k (IOPS)
------ | --- ---- | ---- ----
Read | 134.06 MB/s (33.5k) | 1.75 GB/s (27.3k)
Write | 133.97 MB/s (33.4k) | 1.80 GB/s (28.1k)
Total | 268.04 MB/s (67.0k) | 3.55 GB/s (55.5k)
| |
Block Size | 512k (IOPS) | 1m (IOPS)
------ | --- ---- | ---- ----
Read | 4.74 GB/s (9.2k) | 6.52 GB/s (6.3k)
Write | 5.14 GB/s (10.0k) | 7.27 GB/s (7.1k)
Total | 9.89 GB/s (19.3k) | 13.79 GB/s (13.4k)

                Docker:
                fio Disk Speed Tests (Mixed R/W 50/50) (Partition overlay):
---------------------------------
Block Size | 4k (IOPS) | 64k (IOPS)
------ | --- ---- | ---- ----
Read | 416.23 MB/s (104.0k) | 5.32 GB/s (83.2k)
Write | 415.96 MB/s (103.9k) | 5.48 GB/s (85.6k)
Total | 832.20 MB/s (208.0k) | 10.81 GB/s (168.9k)
| |
Block Size | 512k (IOPS) | 1m (IOPS)
------ | --- ---- | ---- ----
Read | 11.97 GB/s (23.3k) | 14.16 GB/s (13.8k)
Write | 12.99 GB/s (25.3k) | 15.79 GB/s (15.4k)
Total | 24.96 GB/s (48.7k) | 29.95 GB/s (29.2k)

                The test are shorter; but representative; longer duration for example with container it can run with close 1000MiB/s, and occasional drops to 300MiBs. Native block performance is ~3000MB/s.
                Long duration test can be launched via:
                fio --name=rand_rw_512k --ioengine=libaio --rw=randrw --rwmixread=50 --bs=512k --iodepth=64 --numjobs=2 --size=10G --runtime=3600 --time_based --gtod_reduce=1 --direct=1 --filename=./test.fio --group_reporting

                Instruments only has shown pwritev calls for the most part from an IO thread:
                Image
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