What disk read speed is needed for Ardour sessions

Good afternoon
I have been getting a lot of disk too slow messages coming up in fairly modest Ardour (7.5 dbg versions) sessions.
SlowDiskMsg0723

My SSD passes smartctl short tests without any errors and I have run hdparm with the following results:
/dev/sda:
Timing O_DIRECT cached reads: 728 MB in 2.00 seconds = 363.63 MB/sec
Timing O_DIRECT disk reads: 1348 MB in 3.00 seconds = 448.85 MB/sec

The computer is a 2017 Thinkstation

My question is, roughly how many mono audio tracks, midi instruments or fx plugins should I expect to run smoothly based on these results?

Many thanks

Disk speed has absolutely no impact on MIDI Instruments of FX plugins. Zero. Nada.

The theoretical disk speeds you have are enough to handle hundreds of tracks:

mono audio = 32 bits per sample * sample rate = 4 * 48000 = 192,000 bytes/second

So your disks could theoretically support thousands of tracks.

However, streaming disk rates are an indicator of the upper limit on performance, and many other things can affect how fast data can actually be read from a given file. One limitation can be disk fragmentation - much less of an issue on Linux than it was on Windows, but it can still cause dramatic slow downs even with SSDs (which not really “seek”). Another limitation is the performance of the disk i/o scheduler - your disk may be able to provide the data fast enough, but the i/o scheduling may not occur “on time”.

In the end, Ardour is more or less the only tester for Ardour performance. We do have standalone audio file I/O testing tools, but they also tend to test the upper limit, not what happens with a given file on a given disk at a particular time.

Thanks for this info Paul.
Is it worth me trying your i/o tools? I really need to get my system good enough for working with other people
I just want to share the plugin list from the session that screenshot came from:
PluginsintooSlow
There’s 5 mono audio tracks in the session, which is about 4 mins long altogether.
Session rate is 48k
I do take on board what you said about midi instruments and plugins, I just cant understand whats wrong for me

I’m not great with diagnosing this type of stuff but you should definitely NOT be getting those disk errors with Ardour sessions like that. My main Studio box (An old i5 reseller DELL optiplex) is still running 7200rpm SATA HDD’s and I don’t get errors like that on large Audio sessions with 24 tracks+

I would definitely Back Up your important data and run the SMART “GSmartControl” tools on your drives (I think they are included in AV Linux by default) even though your short tests look OK your SSD could be on it’s way out, some SSD’s (Samsung EVO as a recent example) have horrible performance lifespans sadly…

It’s a huge longshot but if the drive is going bad perhaps it may shed some light on the high number of Crashes that have been happening but to be clear I’m am no diagnostic wizard.

Thanks Glen
I will do this
Meanwhile, I have just run health-check on this session, which gave the disk too slow message when simply playing the session and got this output:

$ sudo health-check -p 5508

CPU usage (in terms of 1 CPU):
PID Process USR% SYS% TOTAL% Duration
5508 ardour-7.5.227 41.47 1.25 42.72 60.00 (high load)

Page Faults:
PID Process Minor/sec Major/sec Total/sec
5508 ardour-7.5.227 140.97 0.20 141.17

Context Switches:
PID Process Voluntary Involuntary Total
Ctxt Sw/Sec Ctxt Sw/Sec Ctxt Sw/Sec
5508 ardour-7.5.227 1737.73 16.90 1754.63 (high)

File I/O operations:
PID Process Count Op Filename
5508 ardour-7.5.227 6 W /home/mel/.xsession-errors
5508 ardour-7.5.227 2 R /home/mel/Music/Audio/endInTears/interchange/endInTears/audiofiles/Take88_bass-1.wav
5508 ardour-7.5.227 2 R /home/mel/Music/Audio/endInTears/interchange/endInTears/audiofiles/Take139_gvox1-1.wav
5508 ardour-7.5.227 2 R /home/mel/Music/Audio/endInTears/interchange/endInTears/audiofiles/Take96_gtr1-1.wav
5508 ardour-7.5.227 2 C /home/mel/Music/Audio/endInTears/peaks/cf88c55337d51faa0ef3e2a41a2eadc4a9a19532.peak
5508 ardour-7.5.227 2 O /home/mel/Music/Audio/endInTears/peaks/cf88c55337d51faa0ef3e2a41a2eadc4a9a19532.peak
5508 ardour-7.5.227 2 C /home/mel/Music/Audio/endInTears/peaks/d830640e4b9e2283c360bd75ae16996a18453875.peak
5508 ardour-7.5.227 2 O /home/mel/Music/Audio/endInTears/peaks/d830640e4b9e2283c360bd75ae16996a18453875.peak
5508 ardour-7.5.227 1 R /home/mel/Music/Audio/endInTears/interchange/endInTears/audiofiles/Take68_bv 2-1.wav
5508 ardour-7.5.227 1 R /home/mel/Music/Audio/endInTears/interchange/endInTears/audiofiles/Take58_bv0-1.wav
5508 ardour-7.5.227 1 R /home/mel/Music/Audio/endInTears/interchange/endInTears/audiofiles/Take85_bass-1.wav
5508 ardour-7.5.227 1 C /home/mel/Music/Audio/endInTears/peaks/4da898bb12737317dd4f1c6dbc546284e197a72f.peak
5508 ardour-7.5.227 1 O /home/mel/Music/Audio/endInTears/peaks/4da898bb12737317dd4f1c6dbc546284e197a72f.peak
5508 ardour-7.5.227 1 C /home/mel/Music/Audio/endInTears/peaks/e8aa31c6730db2a020030933088faafe1b3e75f2.peak
5508 ardour-7.5.227 1 O /home/mel/Music/Audio/endInTears/peaks/e8aa31c6730db2a020030933088faafe1b3e75f2.peak
5508 ardour-7.5.227 1 C /home/mel/Music/Audio/endInTears/peaks/30f1413a7761db4c51cd8da35d093591f7560aa1.peak
5508 ardour-7.5.227 1 O /home/mel/Music/Audio/endInTears/peaks/30f1413a7761db4c51cd8da35d093591f7560aa1.peak
5508 ardour-7.5.227 1 C /home/mel/Music/Audio/endInTears/peaks/7428bc9795a4abd6fcaa42843135105b0d8a8a0c.peak
5508 ardour-7.5.227 1 O /home/mel/Music/Audio/endInTears/peaks/7428bc9795a4abd6fcaa42843135105b0d8a8a0c.peak
5508 ardour-7.5.227 1 C /home/mel/Music/Audio/endInTears/peaks/2d8559736d6de7409c174bc4d811621032d3ff51.peak
5508 ardour-7.5.227 1 O /home/mel/Music/Audio/endInTears/peaks/2d8559736d6de7409c174bc4d811621032d3ff51.peak
5508 ardour-7.5.227 1 C /home/mel/Music/Audio/endInTears/peaks/ca6a11dbbbe09425217011257294630f94ea7024.peak
5508 ardour-7.5.227 1 O /home/mel/Music/Audio/endInTears/peaks/ca6a11dbbbe09425217011257294630f94ea7024.peak
5508 ardour-7.5.227 1 C /home/mel/Music/Audio/endInTears/peaks/2f56ad17ab36c5a33dd34119f8e8ce8c339ffa11.peak
5508 ardour-7.5.227 1 O /home/mel/Music/Audio/endInTears/peaks/2f56ad17ab36c5a33dd34119f8e8ce8c339ffa11.peak
5508 ardour-7.5.227 1 C /home/mel/Music/Audio/endInTears/peaks/3d2ef5836d146ea8aa35506c9b1400967aafc854.peak
5508 ardour-7.5.227 1 O /home/mel/Music/Audio/endInTears/peaks/3d2ef5836d146ea8aa35506c9b1400967aafc854.peak
5508 ardour-7.5.227 1 C /home/mel/Music/Audio/endInTears/peaks/0d4b28ef8ee9bfb9716c27606d154ceb440ebf54.peak
5508 ardour-7.5.227 1 O /home/mel/Music/Audio/endInTears/peaks/0d4b28ef8ee9bfb9716c27606d154ceb440ebf54.peak
5508 ardour-7.5.227 1 O /usr/share/fonts/truetype/ttf-bitstream-vera/VeraMono.ttf
5508 ardour-7.5.227 1 C /usr/share/fonts/truetype/ttf-bitstream-vera/VeraSe.ttf
5508 ardour-7.5.227 1 O /opt/Ardour-7.5.227-dbg/share/ArdourSans.ttf
5508 ardour-7.5.227 1 C /usr/share/fonts/truetype/ttf-bitstream-vera/VeraMono.ttf
Total 45
Op: O=Open, R=Read, W=Write, C=Close

File I/O Operations per second:
PID Process Open Close Read Write
5508 ardour-7.5.227 0.25 0.25 0.15 0.10

System calls traced:
PID Process Syscall Count Rate/Sec Total μSecs % Call Time
5508 ardour-7.5.227 recvmsg 25198 419.9664 208134 0.3637
5508 ardour-7.5.227 poll 13928 232.1332 56904279 99.4439
5508 ardour-7.5.227 getpid 3144 52.4000 16346 0.0286
5508 ardour-7.5.227 writev 3040 50.6666 39835 0.0696
5508 ardour-7.5.227 sched_yield 1572 26.2000 8229 0.0144
5508 ardour-7.5.227 read 935 15.5833 6347 0.0111
5508 ardour-7.5.227 ioctl 539 8.9833 25694 0.0449
5508 ardour-7.5.227 write 523 8.7167 3984 0.0070
5508 ardour-7.5.227 stat 73 1.2167 1097 0.0019
5508 ardour-7.5.227 mmap 18 0.3000 339 0.0006
5508 ardour-7.5.227 close 18 0.3000 171 0.0003
5508 ardour-7.5.227 openat 18 0.3000 232 0.0004
5508 ardour-7.5.227 munmap 15 0.2500 241 0.0004
5508 ardour-7.5.227 futex 7 0.1167 53 0.0001
5508 ardour-7.5.227 brk 6 0.1000 60 0.0001
5508 ardour-7.5.227 fcntl 5 0.0833 31 0.0001
5508 ardour-7.5.227 fstat 2 0.0333 14 0.0000
5508 ardour-7.5.227 restart_syscall 1 0.0167 7425 0.0130
Total 49042 817.3661 57222511

Top polling system calls:
PID Process Syscall Rate/Sec Infinite Zero Minimum Maximum Average
Timeouts Timeouts Timeout Timeout Timeout
5508 ardour-7.5.227 poll 232.1332 4634 3271 0.0 sec 1.0 sec 23.2 msec

Distribution of poll timeout times:
10.0 100.0 1.0 10.0 100.0 1.0 10.0 100.0
up to to to to to to to to or more
Zero 9.9 99.9 999.9 9.9 99.9 999.9 9.9 99.9 Infinite
PID Process Syscall sec usec usec usec msec msec msec sec sec sec Wait
5508 ardour-7.5.227 poll 3271 - - - 2980 2781 - 262 - - 4634

Polling system call analysis:
ardour-7.5.227 (5508), poll:
3211 immediate timed out calls with zero timeout (non-blocking peeks)
1518 repeated timed out polled calls with non-zero timeouts (light polling)
896 repeated immediate timed out polled calls with zero timeouts (heavy polling peeks)

Filesystem Syncs:
None.

Inotify watches added:
None.

Memory:
Per Process Memory (K):
PID Process Type Size RSS PSS
5508 ardour-7.5.227 Stack 164 144 144
5508 ardour-7.5.227 Heap 3205280 532300 532300
5508 ardour-7.5.227 Mapped 524556 176112 158587

Change in memory (K/second):
PID Process Type Size RSS PSS
5508 ardour-7.5.227 Heap 111.67 50.00 50.00 (growing moderately fast)
5508 ardour-7.5.227 Mapped 151.87 162.27 155.32 (growing fast)

Heap Change via brk():
PID brk Count Change (K) Rate (K/Sec)
5508 ardour-7.5.227 6 6564 109.40 (growing moderately fast)

Memory Change via mmap() and munmap():
PID mmaps munmaps Change (K) Rate (K/Sec)
5508 ardour-7.5.227 18 15 9111 151.86 (growing moderately fast)

Open Network Connections:
PID Process Proto Send Receive Address
5508 ardour-7.5.227 UNIX 0.00 B 42.15 K @/tmp/.X11-unix/X0
5508 ardour-7.5.227 UNIX 0.00 B 16.38 K /tmp/dbus-4wmxTX0ogB
5508 ardour-7.5.227 UNIX 0.00 B 0.00 B @/tmp/.ICE-unix/2988
5508 ardour-7.5.227 NETLINK 0.00 B 0.00 B netlink:[70515]
5508 ardour-7.5.227 UNIX 0.00 B 0.00 B /tmp/dbus-dphmuGOsRq
5508 ardour-7.5.227 UNIX 0.00 B 0.00 B 00000000000000000000000:AA5B 00000000000000000000000000000000:0000 07 00000000:00000000 00:00000000 00000000 110 0 18520 2 000000007dd06a62 0

Total 0.00 B 58.53 K

I dont know what that all means, maybe someone more technical knows?

The strange thing is, everything except Ardour is working well. Even Kdenlive which I have previously found to be super flaky, works pretty good on this system.

Next, I will try the GSmartControl tools and report back
Thanks again

Heres the GSmartControl initial results. Im running an extended test now and will post when its done:
smartctl 7.2 2020-12-30 r5155 [x86_64-linux-6.0.0-10.1-liquorix-amd64] (local build)
Copyright (C) 2002-20, Bruce Allen, Christian Franke, www.smartmontools.org

=== START OF INFORMATION SECTION ===
Device Model: SanDisk SD6SB2M512G1001
Serial Number: 150774400222
LU WWN Device Id: 5 001b44 e266fc0de
Firmware Version: X210801
User Capacity: 512,110,190,592 bytes [512 GB]
Sector Size: 512 bytes logical/physical
Rotation Rate: Solid State Device
Form Factor: 5.25 inches
TRIM Command: Available, deterministic, zeroed
Device is: Not in smartctl database [for details use: -P showall]
ATA Version is: ATA8-ACS T13/1699-D revision 6
SATA Version is: SATA 3.0, 6.0 Gb/s (current: 6.0 Gb/s)
Local Time is: Sun Jul 30 21:16:37 2023 BST
SMART support is: Available - device has SMART capability.
SMART support is: Enabled
AAM feature is: Unavailable
APM level is: 254 (maximum performance)
Rd look-ahead is: Enabled
Write cache is: Enabled
DSN feature is: Unavailable
ATA Security is: Disabled, frozen [SEC2]

=== START OF READ SMART DATA SECTION ===
SMART overall-health self-assessment test result: PASSED

General SMART Values:
Offline data collection status: (0x00) Offline data collection activity
was never started.
Auto Offline Data Collection: Disabled.
Self-test execution status: ( 0) The previous self-test routine completed
without error or no self-test has ever
been run.
Total time to complete Offline
data collection: ( 0) seconds.
Offline data collection
capabilities: (0x11) SMART execute Offline immediate.
No Auto Offline data collection support.
Suspend Offline collection upon new
command.
No Offline surface scan supported.
Self-test supported.
No Conveyance Self-test supported.
No Selective Self-test supported.
SMART capabilities: (0x0003) Saves SMART data before entering
power-saving mode.
Supports SMART auto save timer.
Error logging capability: (0x01) Error logging supported.
General Purpose Logging supported.
Short self-test routine
recommended polling time: ( 2) minutes.
Extended self-test routine
recommended polling time: ( 10) minutes.

SMART Attributes Data Structure revision number: 4
Vendor Specific SMART Attributes with Thresholds:
ID# ATTRIBUTE_NAME FLAGS VALUE WORST THRESH FAIL RAW_VALUE
5 Reallocated_Sector_Ct -O–CK 100 100 — - 0
9 Power_On_Hours -O–CK 253 100 — - 22254
12 Power_Cycle_Count -O–CK 100 100 — - 797
166 Unknown_Attribute -O–CK 100 100 — - 22
167 Unknown_Attribute -O–CK 100 100 — - 32
168 Unknown_Attribute -O–CK 100 100 — - 198
169 Unknown_Attribute -O–CK 100 100 — - 651
171 Unknown_Attribute -O–CK 100 100 — - 0
172 Unknown_Attribute -O–CK 100 100 — - 0
173 Unknown_Attribute -O–CK 100 100 — - 90
174 Unknown_Attribute -O–CK 100 100 — - 127
187 Reported_Uncorrect -O–CK 100 100 — - 0
194 Temperature_Celsius -O—K 071 136 — - 29 (0 136 0 19 0)
199 UDMA_CRC_Error_Count -O–CK 100 100 — - 0
230 Unknown_SSD_Attribute -O–CK 100 100 — - 768
232 Available_Reservd_Space PO–CK 100 100 004 - 100
233 Media_Wearout_Indicator -O–CK 100 100 — - 768
241 Total_LBAs_Written ----CK 253 253 — - 20542
242 Total_LBAs_Read ----CK 253 253 — - 11334
243 Unknown_Attribute -O–CK 100 100 — - 0
||||||_ K auto-keep
|||||__ C event count
||||___ R error rate
|||____ S speed/performance
||_____ O updated online
|______ P prefailure warning

General Purpose Log Directory Version 1
SMART Log Directory Version 1 [multi-sector log support]
Address Access R/W Size Description
0x00 GPL,SL R/O 1 Log Directory
0x01 SL R/O 1 Summary SMART error log
0x02 SL R/O 2 Comprehensive SMART error log
0x03 GPL R/O 1 Ext. Comprehensive SMART error log
0x04 GPL,SL R/O 8 Device Statistics log
0x06 SL R/O 1 SMART self-test log
0x07 GPL R/O 1 Extended self-test log
0x10 GPL R/O 1 NCQ Command Error log
0x11 GPL R/O 1 SATA Phy Event Counters log
0x30 GPL,SL R/O 9 IDENTIFY DEVICE data log
0x80-0x9f GPL,SL R/W 16 Host vendor specific log

SMART Extended Comprehensive Error Log Version: 1 (1 sectors)
No Errors Logged

SMART Extended Self-test Log Version: 1 (1 sectors)
Num Test_Description Status Remaining LifeTime(hours) LBA_of_first_error

1 Extended offline Completed without error 00% 22253 -

2 Conveyance offline Completed without error 00% 0 -

3 Short offline Completed without error 00% 22252 -

4 Short offline Completed without error 00% 22252 -

Selective Self-tests/Logging not supported

SCT Commands not supported

Device Statistics (GP Log 0x04)
Page Offset Size Value Flags Description
0x07 ===== = = === == Solid State Device Statistics (rev 1) ==
0x07 0x008 1 3 — Percentage Used Endurance Indicator
|||_ C monitored condition met
||__ D supports DSN
|___ N normalized value

SATA Phy Event Counters (GP Log 0x11)
ID Size Value Description
0x0001 4 0 Command failed due to ICRC error
0x0002 4 0 R_ERR response for data FIS
0x0005 4 0 R_ERR response for non-data FIS
0x000a 4 3 Device-to-host register FISes sent due to a COMRESET

Heres the result of the extended test, which it passed without any errors

smartctl 7.2 2020-12-30 r5155 [x86_64-linux-6.0.0-10.1-liquorix-amd64] (local build)
Copyright (C) 2002-20, Bruce Allen, Christian Franke, www.smartmontools.org

=== START OF INFORMATION SECTION ===
Device Model: SanDisk SD6SB2M512G1001
Serial Number: 150774400222
LU WWN Device Id: 5 001b44 e266fc0de
Firmware Version: X210801
User Capacity: 512,110,190,592 bytes [512 GB]
Sector Size: 512 bytes logical/physical
Rotation Rate: Solid State Device
Form Factor: 5.25 inches
TRIM Command: Available, deterministic, zeroed
Device is: Not in smartctl database [for details use: -P showall]
ATA Version is: ATA8-ACS T13/1699-D revision 6
SATA Version is: SATA 3.0, 6.0 Gb/s (current: 6.0 Gb/s)
Local Time is: Sun Jul 30 21:28:18 2023 BST
SMART support is: Available - device has SMART capability.
SMART support is: Enabled
AAM feature is: Unavailable
APM level is: 254 (maximum performance)
Rd look-ahead is: Enabled
Write cache is: Enabled
DSN feature is: Unavailable
ATA Security is: Disabled, frozen [SEC2]

=== START OF READ SMART DATA SECTION ===
SMART overall-health self-assessment test result: PASSED

General SMART Values:
Offline data collection status: (0x00) Offline data collection activity
was never started.
Auto Offline Data Collection: Disabled.
Self-test execution status: ( 0) The previous self-test routine completed
without error or no self-test has ever
been run.
Total time to complete Offline
data collection: ( 0) seconds.
Offline data collection
capabilities: (0x11) SMART execute Offline immediate.
No Auto Offline data collection support.
Suspend Offline collection upon new
command.
No Offline surface scan supported.
Self-test supported.
No Conveyance Self-test supported.
No Selective Self-test supported.
SMART capabilities: (0x0003) Saves SMART data before entering
power-saving mode.
Supports SMART auto save timer.
Error logging capability: (0x01) Error logging supported.
General Purpose Logging supported.
Short self-test routine
recommended polling time: ( 2) minutes.
Extended self-test routine
recommended polling time: ( 10) minutes.

SMART Attributes Data Structure revision number: 4
Vendor Specific SMART Attributes with Thresholds:
ID# ATTRIBUTE_NAME FLAGS VALUE WORST THRESH FAIL RAW_VALUE
5 Reallocated_Sector_Ct -O–CK 100 100 — - 0
9 Power_On_Hours -O–CK 253 100 — - 22254
12 Power_Cycle_Count -O–CK 100 100 — - 797
166 Unknown_Attribute -O–CK 100 100 — - 22
167 Unknown_Attribute -O–CK 100 100 — - 32
168 Unknown_Attribute -O–CK 100 100 — - 198
169 Unknown_Attribute -O–CK 100 100 — - 651
171 Unknown_Attribute -O–CK 100 100 — - 0
172 Unknown_Attribute -O–CK 100 100 — - 0
173 Unknown_Attribute -O–CK 100 100 — - 90
174 Unknown_Attribute -O–CK 100 100 — - 127
187 Reported_Uncorrect -O–CK 100 100 — - 0
194 Temperature_Celsius -O—K 064 136 — - 36 (0 136 0 19 0)
199 UDMA_CRC_Error_Count -O–CK 100 100 — - 0
230 Unknown_SSD_Attribute -O–CK 100 100 — - 768
232 Available_Reservd_Space PO–CK 100 100 004 - 100
233 Media_Wearout_Indicator -O–CK 100 100 — - 769
241 Total_LBAs_Written ----CK 253 253 — - 20542
242 Total_LBAs_Read ----CK 253 253 — - 11334
243 Unknown_Attribute -O–CK 100 100 — - 0
||||||_ K auto-keep
|||||__ C event count
||||___ R error rate
|||____ S speed/performance
||_____ O updated online
|______ P prefailure warning

General Purpose Log Directory Version 1
SMART Log Directory Version 1 [multi-sector log support]
Address Access R/W Size Description
0x00 GPL,SL R/O 1 Log Directory
0x01 SL R/O 1 Summary SMART error log
0x02 SL R/O 2 Comprehensive SMART error log
0x03 GPL R/O 1 Ext. Comprehensive SMART error log
0x04 GPL,SL R/O 8 Device Statistics log
0x06 SL R/O 1 SMART self-test log
0x07 GPL R/O 1 Extended self-test log
0x10 GPL R/O 1 NCQ Command Error log
0x11 GPL R/O 1 SATA Phy Event Counters log
0x30 GPL,SL R/O 9 IDENTIFY DEVICE data log
0x80-0x9f GPL,SL R/W 16 Host vendor specific log

SMART Extended Comprehensive Error Log Version: 1 (1 sectors)
No Errors Logged

SMART Extended Self-test Log Version: 1 (1 sectors)
Num Test_Description Status Remaining LifeTime(hours) LBA_of_first_error

1 Extended offline Completed without error 00% 22254 -

2 Extended offline Completed without error 00% 22253 -

3 Conveyance offline Completed without error 00% 0 -

4 Short offline Completed without error 00% 22252 -

5 Short offline Completed without error 00% 22252 -

Selective Self-tests/Logging not supported

SCT Commands not supported

Device Statistics (GP Log 0x04)
Page Offset Size Value Flags Description
0x07 ===== = = === == Solid State Device Statistics (rev 1) ==
0x07 0x008 1 3 — Percentage Used Endurance Indicator
|||_ C monitored condition met
||__ D supports DSN
|___ N normalized value

SATA Phy Event Counters (GP Log 0x11)
ID Size Value Description
0x0001 4 0 Command failed due to ICRC error
0x0002 4 0 R_ERR response for data FIS
0x0005 4 0 R_ERR response for non-data FIS
0x000a 4 3 Device-to-host register FISes sent due to a COMRESET

Maybe you should try a non-debug version of Ardour

Actually, the opposite. If this problem is easily repeatable, running ardour on the command like this could be interesting:

% /path/to/ardour -D butler,diskio >/tmp/out 2>&1

then making /tmp/out available

Thanks Paul
Here’s [temp/out](7.22 MB file on MEGA

What can you tell me about the “bv0” track?

Its a backing vocal track. I sung a chorus and copied and pasted it twice down the song.
I also probably sung over one of the choruses as well to improve the performance.
Is this what you were asking?
Many thanks for your help

Hey Paul
I’ve noticed there’s an audible glitch at 3m9s in the gvox1 track and just now Ive had a crash at this time

Sadly I can’t do anything with information like that (the “crash report”)

Ive now removed that track entirely but crash is still happening
I will restart the computer and will do another /tmp/out and link it

We need to get you using a custom build with more debug output. Not sure of the best way to do that. AFAIK, you use the nightly builds from ardour.org ?

Yes Im using nightlies from here and have been for all v7 due to problems
Heres the latest out. It crashed in a few seconds of pressing play
Thanks for all your help, I really appreciate it

Alas, standard output is not useful for crashes. The “out” file was to try to diagnose why you get these disk speed issues, and although it provides a vague hint, it’s not enough information.

Crashes need to be repeatable and have backtraces to have a chance of being resolvable.

I record to a NAS volume mounted using NFS and have never experienced any performance issues with the disk subsystem.

Do you want me to do another dbg?