GDB MI command -thread-info takes about 1 second to complete

[dosvidos]

I'm using GDB 7.10 from NDK r11b for Windows 64-bit and I've noticed that -thread-info command takes a lot of time for processing compared to other GDB MI commands - more than one second on Nexus 7 2013 device running API21 and bit less on a newer hardware. I suppose that's due to the fact that it also reports the top stack frame for each thread of execution. That's unfortunate, because sometimes front-end needs to get thread names really quick, and 1 second delay hurts UX. Maybe there's a faster way to query for a thread names?
Call -thread-info for each thread id in a loop is even slower, though.

2016-03-31 21:36:20.1611[GDB] cmd: "357-thread-info"
2016-03-31 21:36:20.8566[GDB] stdout: 357^done,threads=[{id="31",target-id="Thread 5962",frame={level="0",addr="0x406f260c",func="syscall",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="1"},{id="30",target-id="Thread 5961",frame={level="0",addr="0x4071cc2c",func="__pselect6",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="1"},{id="29",target-id="Thread 5960",frame={level="0",addr="0x4071cc2c",func="__pselect6",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="1"},{id="28",target-id="Thread 5959",frame={level="0",addr="0x406f260c",func="syscall",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="1"},{id="27",target-id="Thread 5958",frame={level="0",addr="0x406f260c",func="syscall",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="1"},{id="26",target-id="Thread 5957",frame={level="0",addr="0x406f260c",func="syscall",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="1"},{id="25",target-id="Thread 5956",frame={level="0",addr="0x4071c2bc",func="nanosleep",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="1"},{id="24",target-id="Thread 5955",frame={level="0",addr="0x6e15e542",func="??",args=[],from="sysroot\symbols32\system\vendor\lib\libglcore.so"},state="stopped",core="0"},{id="23",target-id="Thread 5954",frame={level="0",addr="0x406f260c",func="syscall",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="0"},{id="22",target-id="Thread 5953",frame={level="0",addr="0x406f260c",func="syscall",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="1"},{id="21",target-id="Thread 5952",frame={level="0",addr="0x406f260c",func="syscall",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="0"},{id="20",target-id="Thread 5950",frame={level="0",addr="0x406f260c",func="syscall",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="1"},{id="19",target-id="Thread 5949",frame={level="0",addr="0x406f260c",func="syscall",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="0"},{id="18",target-id="Thread 5948",frame={level="0",addr="0x406f260c",func="syscall",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="0"},{id="17",target-id="Thread 5946",frame={level="0",addr="0x406f260c",func="syscall",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="1"},{id="16",target-id="Thread 5945",frame={level="0",addr="0x406f260c",func="syscall",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="0"},{id="15",target-id="Thread 5944",frame={level="0",addr="0x406f260c",func="syscall",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="0"},{id="14",target-id="Thread 5943",frame={level="0",addr="0x406f260c",func="syscall",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="1"},{id="13",target-id="Thread 5951",frame={level="0",addr="0x4071c6b8",func="__ioctl",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="1"},{id="12",target-id="Thread 5940",frame={level="0",addr="0x4071c6b8",func="__ioctl",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="0"},{id="11",target-id="Thread 4290",frame={level="0",addr="0x4071c868",func="__epoll_pwait",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="1"},{id="10",target-id="Thread 4289",frame={level="0",addr="0x57033264",func="UParticleSystemComponent::TickComponent",args=[{name="this",value="0x80066000"},{name="DeltaTime",value="0.0320000015"},{name="TickType",value="LEVELTICK_All"},{name="ThisTickFunction",value="0x0"}],file="C:\UnrealEngine-4.10\Engine\Source\Runtime\Engine\Private\Particles/ParticleComponents.cpp",fullname="C:\UnrealEngine-4.10\Engine\Source\Runtime\Engine\Private\Particles\ParticleComponents.cpp",line="3577"},state="stopped",core="1"},{id="9",target-id="Thread 4253",frame={level="0",addr="0x4071c6b8",func="__ioctl",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="1"},{id="8",target-id="Thread 4252",frame={level="0",addr="0x4071c6b8",func="__ioctl",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="1"},{id="7",target-id="Thread 4251",frame={level="0",addr="0x406f260c",func="syscall",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="1"},{id="6",target-id="Thread 4250",frame={level="0",addr="0x406f260c",func="syscall",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="0"},{id="5",target-id="Thread 4249",frame={level="0",addr="0x406f260c",func="syscall",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="1"},{id="4",target-id="Thread 4248",frame={level="0",addr="0x406f260c",func="syscall",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="0"},{id="3",target-id="Thread 4247",frame={level="0",addr="0x4071c2fc",func="recvmsg",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="1"},{id="2",target-id="Thread 4246",frame={level="0",addr="0x4071bfe8",func="__rt_sigtimedwait",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="1"},{id="1",target-id="Thread 4241",frame={level="0",addr="0x4071c868",func="__epoll_pwait",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="1"}],current-thread-id="10"
2016-03-31 21:36:41.8705[GDB] cmd: "358-thread-info"
2016-03-31 21:36:42.5285[GDB] stdout: 358^done,threads=[{id="31",target-id="Thread 5962",frame={level="0",addr="0x406f260c",func="syscall",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="1"},{id="30",target-id="Thread 5961",frame={level="0",addr="0x4071cc2c",func="__pselect6",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="1"},{id="29",target-id="Thread 5960",frame={level="0",addr="0x4071cc2c",func="__pselect6",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="1"},{id="28",target-id="Thread 5959",frame={level="0",addr="0x406f260c",func="syscall",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="1"},{id="27",target-id="Thread 5958",frame={level="0",addr="0x406f260c",func="syscall",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="1"},{id="26",target-id="Thread 5957",frame={level="0",addr="0x406f260c",func="syscall",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="1"},{id="25",target-id="Thread 5956",frame={level="0",addr="0x4071c2bc",func="nanosleep",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="1"},{id="24",target-id="Thread 5955",frame={level="0",addr="0x6e15e542",func="??",args=[],from="sysroot\symbols32\system\vendor\lib\libglcore.so"},state="stopped",core="0"},{id="23",target-id="Thread 5954",frame={level="0",addr="0x406f260c",func="syscall",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="0"},{id="22",target-id="Thread 5953",frame={level="0",addr="0x406f260c",func="syscall",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="1"},{id="21",target-id="Thread 5952",frame={level="0",addr="0x406f260c",func="syscall",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="0"},{id="20",target-id="Thread 5950",frame={level="0",addr="0x406f260c",func="syscall",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="1"},{id="19",target-id="Thread 5949",frame={level="0",addr="0x406f260c",func="syscall",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="0"},{id="18",target-id="Thread 5948",frame={level="0",addr="0x406f260c",func="syscall",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="0"},{id="17",target-id="Thread 5946",frame={level="0",addr="0x406f260c",func="syscall",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="1"},{id="16",target-id="Thread 5945",frame={level="0",addr="0x406f260c",func="syscall",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="0"},{id="15",target-id="Thread 5944",frame={level="0",addr="0x406f260c",func="syscall",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="0"},{id="14",target-id="Thread 5943",frame={level="0",addr="0x406f260c",func="syscall",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="1"},{id="13",target-id="Thread 5951",frame={level="0",addr="0x4071c6b8",func="__ioctl",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="1"},{id="12",target-id="Thread 5940",frame={level="0",addr="0x4071c6b8",func="__ioctl",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="0"},{id="11",target-id="Thread 4290",frame={level="0",addr="0x4071c868",func="__epoll_pwait",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="1"},{id="10",target-id="Thread 4289",frame={level="0",addr="0x57033264",func="UParticleSystemComponent::TickComponent",args=[{name="this",value="0x80066000"},{name="DeltaTime",value="0.0320000015"},{name="TickType",value="LEVELTICK_All"},{name="ThisTickFunction",value="0x0"}],file="C:\UnrealEngine-4.10\Engine\Source\Runtime\Engine\Private\Particles/ParticleComponents.cpp",fullname="C:\UnrealEngine-4.10\Engine\Source\Runtime\Engine\Private\Particles\ParticleComponents.cpp",line="3577"},state="stopped",core="1"},{id="9",target-id="Thread 4253",frame={level="0",addr="0x4071c6b8",func="__ioctl",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="1"},{id="8",target-id="Thread 4252",frame={level="0",addr="0x4071c6b8",func="__ioctl",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="1"},{id="7",target-id="Thread 4251",frame={level="0",addr="0x406f260c",func="syscall",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="1"},{id="6",target-id="Thread 4250",frame={level="0",addr="0x406f260c",func="syscall",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="0"},{id="5",target-id="Thread 4249",frame={level="0",addr="0x406f260c",func="syscall",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="1"},{id="4",target-id="Thread 4248",frame={level="0",addr="0x406f260c",func="syscall",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="0"},{id="3",target-id="Thread 4247",frame={level="0",addr="0x4071c2fc",func="recvmsg",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="1"},{id="2",target-id="Thread 4246",frame={level="0",addr="0x4071bfe8",func="__rt_sigtimedwait",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="1"},{id="1",target-id="Thread 4241",frame={level="0",addr="0x4071c868",func="__epoll_pwait",args=[],from="sysroot\symbols32\system\lib\libc.so"},state="stopped",core="1"}],current-thread-id="10"

[jmgao]

I don't think there's much we can do about this, maybe file an upstream bug/feature request? The gdb documentation suggests for a related operation that you should cache the results. If you use async, I think you should be able to notice and query threads for their name as soon as you get a thread-created notification.