Memory leak in widget.Table due to constantly creating cells to cache.Renderer(impl) while table.Refresh() about fyne HOT 13 OPEN

Out of interest can you give it half a chance? Wait until the window is visible and also refresh at less than your screens refresh rate? For example a 100ms delay and then a 20ms ticker?
I don't know if it will be resolved with that but it may be different as the renderers will be properly initialised once drawn.

from fyne.

Out of interest can you give it half a chance? Wait until the window is visible and also refresh at less than your screens refresh rate? For example a 100ms delay and then a 20ms ticker? I don't know if it will be resolved with that but it may be different as the renderers will be properly initialised once drawn.

The testing code just a easy and simple way to reproduce the problem, not a regular scene. Actually I'm using it a very low refresh rate in production environment, such as 2 seconds refresh 4 * 100 cells, but it still take 100mb ram incr every 3 hours.

from fyne.

I think the table code could possibly be improved (looking quickly at the code I don't understand why we need to create a new template cell every refresh) but I don't believe there's a memory leak here. The renderer cache is periodically cleaned out to remove expired renderers for widgets that are not being drawn anymore, so while this will cause memory to go up for a bit, the renderers will eventually be GC'ed. What you may be seeing is Go holding on to more memory than is actually in use by the app too in case it needs to allocate more. Now running refresh every 10 ms will cause a lot of memory to accumulate because IIRC the caches are cleaned every 1 or 2 minutes.

from fyne.

Another thing @ZSA233 if you're updating a table and refreshing for each cell (not sure if you're doing this) - it's better to update all the cells and then refresh the table once. (That is assuming you update all the cells together). In general it's important for performance in Fyne to refresh only when needed, and at the lowest refresh scope too. Basically don't refresh until you want the widget to be redrawn.

from fyne.

I think the table code could possibly be improved (looking quickly at the code I don't understand why we need to create a new template cell every refresh) but I don't believe there's a memory leak here. The renderer cache is periodically cleaned out to remove expired renderers for widgets that are not being drawn anymore, so while this will cause memory to go up for a bit, the renderers will eventually be GC'ed. What you may be seeing is Go holding on to more memory than is actually in use by the app too in case it needs to allocate more. Now running refresh every 10 ms will cause a lot of memory to accumulate because IIRC the caches are cleaned every 1 or 2 minutes.

You are right for the cache cleaning code in the driver, so cache.Renderer() may not be the reason for the memory leak. However, the leak still exists for somewhere, as it persists even after several hours of executing table.Refresh(), even at a low refresh rate.

• It may be help for the debuging, below is my production environment pprof heap top20. (been running for 8 hours)

Showing nodes accounting for 233.01MB, 91.87% of 253.63MB total
Dropped 121 nodes (cum <= 1.27MB)
Showing top 20 nodes out of 143
      flat  flat%   sum%        cum   cum%
   35.51MB 14.00% 14.00%    52.51MB 20.70%  fyne.io/fyne/v2/widget.(*RichText).cachedSegmentVisual
   28.72MB 11.32% 25.32%   163.59MB 64.50%  fyne.io/fyne/v2/internal/cache.Renderer
   26.61MB 10.49% 35.81%    26.61MB 10.49%  github.com/go-text/typesetting/opentype/loader.(*Loader).findTableBuffer
   26.01MB 10.25% 46.07%    28.01MB 11.04%  fyne.io/fyne/v2/widget.NewLabelWithStyle
      18MB  7.10% 53.17%       18MB  7.10%  fyne.io/fyne/v2/widget.NewRichText (inline)
   16.50MB  6.51% 59.67%    16.50MB  6.51%  fyne.io/fyne/v2/canvas.NewText (inline)
   12.51MB  4.93% 64.60%    12.51MB  4.93%  github.com/go-text/typesetting/opentype/tables.(*SimpleGlyph).parsePoints
      12MB  4.73% 69.34%       12MB  4.73%  fyne.io/fyne/v2/canvas.NewRectangle (inline)
      11MB  4.34% 73.67%       11MB  4.34%  runtime.malg
      10MB  3.94% 77.62%       28MB 11.04%  fyne.io/fyne/v2/widget.NewRichTextWithText
    5.50MB  2.17% 79.79%    19.01MB  7.49%  github.com/go-text/typesetting/opentype/tables.(*Glyph).parseData
    4.50MB  1.77% 81.56%     4.50MB  1.77%  time.NewTicker
    4.50MB  1.77% 83.33%     4.50MB  1.77%  fyne.io/fyne/v2/internal/cache.(*expiringCache).setAlive
    4.15MB  1.64% 84.97%     4.15MB  1.64%  github.com/riobard/go-bloom.New
    3.50MB  1.38% 86.35%    15.21MB  6.00%  fyne.io/fyne/v2/widget.(*RichText).updateRowBounds.func1
    3.50MB  1.38% 87.73%     3.50MB  1.38%  fyne.io/fyne/v2/internal/widget.NewSimpleRenderer (inline)
       3MB  1.18% 88.91%    76.01MB 29.97%  fyne.io/fyne/v2/widget.(*RichText).CreateRenderer
       3MB  1.18% 90.10%        3MB  1.18%  fyne.io/fyne/v2/widget.(*BaseWidget).ExtendBaseWidget
    2.50MB  0.99% 91.08%    55.51MB 21.89%  fyne.io/fyne/v2/widget.(*textRenderer).Refresh
       2MB  0.79% 91.87%        2MB  0.79%  fyne.io/fyne/v2/widget.splitLines

• It says 253.63MB total, but it actually takes up almost 700MB, meaning the leak may not be in Go structs, but could be at the cgo level.

from fyne.

This could be a duplicate of text cache issues we are working on, if the text in the cells is changing on each refresh.
I was perhaps diverted from thinking this based on the assertion that it was the create calls being over used that was the source of the issue. On further investigation does it seem like the memory rather than the function calls is the issue being investigated?

from fyne.

Could be, though I still don't think it's an actual memory leak, as the text texture cache is cleaned out on a schedule too. It's an issue of more memory being consumed than needed though since each unique line of text (as opposed to glyph) shown is a unique entry in the texture cache.

from fyne.

It shouldn't grow like the OP is reporting though surely - over hours of usage?

from fyne.

It shouldn't grow like the OP is reporting though surely - over hours of usage?

Yeap,
the OP's testing code may be incorrect for reproducing my prod env problem.
I have been re-testing the OP code for over an hour, the memory usage has been stable, running between 100~200MB, which is not a significant issue. Therefore, I make another test that is closer to the memory issues in prod env:

• running in foreground
• hours of usage
• wrapped widget.Table

testing result

1. Time: Jun 7, 2024 at 1:03am (CST)

PS C:\Users\ZSA> go tool pprof http://127.0.0.1:9996/debug/pprof/heap
Fetching profile over HTTP from http://127.0.0.1:9996/debug/pprof/heap
Saved profile in C:\Users\ZSA\pprof\pprof.___6go_build_test.exe.alloc_objects.alloc_space.inuse_objects.inuse_space.001.pb.gz
File: ___6go_build_test.exe
Build ID: C:\Users\ZSA\AppData\Local\JetBrains\GoLand2024.1\tmp\GoLand\___6go_build_test.exe2024-06-07 00:59:15.714434 +0800 CST
Type: inuse_space
Time: Jun 7, 2024 at 1:03am (CST)
Entering interactive mode (type "help" for commands, "o" for options)
(pprof) top20
Showing nodes accounting for 23784.30kB, 100% of 23784.30kB total
Showing top 20 nodes out of 131
      flat  flat%   sum%        cum   cum%
 9605.13kB 40.38% 40.38%  9605.13kB 40.38%  github.com/go-text/typesetting/opentype/loader.(*Loader).findTableBuffer
 2560.70kB 10.77% 51.15%  2560.70kB 10.77%  fyne.io/fyne/v2/widget.(*RichText).cachedSegmentVisual
 2272.37kB  9.55% 60.70%  2272.37kB  9.55%  fyne.io/fyne/v2/internal/cache.SetFontMetrics
 1056.33kB  4.44% 65.15%  1056.33kB  4.44%  github.com/go-text/typesetting/opentype/tables.ParseBaseArray
 1024.20kB  4.31% 69.45%  1024.20kB  4.31%  fyne.io/fyne/v2/widget.NewLabelWithStyle
 1024.19kB  4.31% 73.76%  8044.71kB 33.82%  fyne.io/fyne/v2/widget.NewRichText (inline)
 1024.06kB  4.31% 78.06%  2048.21kB  8.61%  github.com/go-text/typesetting/opentype/tables.(*Glyph).parseData
  596.16kB  2.51% 80.57%   596.16kB  2.51%  github.com/go-text/typesetting/opentype/api/font/cff.parseIndexContent
  522.70kB  2.20% 82.77%   522.70kB  2.20%  github.com/go-text/typesetting/unicodedata.map.init.0
  513.50kB  2.16% 84.93%   513.50kB  2.16%  image.NewRGBA
  512.44kB  2.15% 87.08%   512.44kB  2.15%  github.com/go-text/typesetting/harfbuzz.newShaperOpentype
  512.17kB  2.15% 89.24%   512.17kB  2.15%  github.com/go-text/typesetting/opentype/api/font.(*Face).getPointsForGlyph
  512.12kB  2.15% 91.39%   512.12kB  2.15%  github.com/go-text/typesetting/harfbuzz.(*otMap).addLookups
  512.10kB  2.15% 93.54%   512.10kB  2.15%  github.com/go-text/typesetting/opentype/tables.(*SimpleGlyph).parsePoints
  512.05kB  2.15% 95.69%   512.05kB  2.15%  regexp/syntax.(*parser).newRegexp
  512.05kB  2.15% 97.85%   512.05kB  2.15%  github.com/go-text/typesetting/opentype/tables.(*CompositeGlyph).parseGlyphs  512.02kB  2.15%   100%   512.02kB  2.15%  fyne.io/fyne/v2/internal/cache.SetCanvasForObject
         0     0%   100% 15578.21kB 65.50%  fyne.io/fyne/v2.MeasureText
         0     0%   100% 16890.72kB 71.02%  fyne.io/fyne/v2/internal/cache.Renderer
         0     0%   100%  2562.25kB 10.77%  fyne.io/fyne/v2/internal/driver.WalkVisibleObjectTree
(pprof)
PS C:\Users\ZSA> tasklist /FI "PID eq 11876"

映像名称                       PID 会话名              会话#       内存使用
========================= ======== ================ =========== ============
___6go_build_test.exe        11876 Console                    1    155,352 K

2. Time: Jun 7, 2024 at 11:56am (CST)

PS C:\Users\ZSA> go tool pprof http://127.0.0.1:9996/debug/pprof/heap
Fetching profile over HTTP from http://127.0.0.1:9996/debug/pprof/heap
Saved profile in C:\Users\ZSA\pprof\pprof.___6go_build_test.exe.alloc_objects.alloc_space.inuse_objects.inuse_space.005.pb.gz
File: ___6go_build_test.exe
Build ID: C:\Users\ZSA\AppData\Local\JetBrains\GoLand2024.1\tmp\GoLand\___6go_build_test.exe2024-06-07 00:59:15.714434 +0800 CST
Type: inuse_space
Time: Jun 7, 2024 at 11:56am (CST)
Entering interactive mode (type "help" for commands, "o" for options)
(pprof) top20
Showing nodes accounting for 440.77MB, 96.11% of 458.63MB total
Dropped 86 nodes (cum <= 2.29MB)
Showing top 20 nodes out of 82
      flat  flat%   sum%        cum   cum%
  135.54MB 29.55% 29.55%   173.04MB 37.73%  fyne.io/fyne/v2/widget.(*RichText).cachedSegmentVisual
   69.51MB 15.16% 44.71%    69.51MB 15.16%  fyne.io/fyne/v2/widget.NewLabelWithStyle (inline)
   55.01MB 11.99% 56.70%    61.87MB 13.49%  fyne.io/fyne/v2/widget.NewRichText (inline)
      36MB  7.85% 64.55%       36MB  7.85%  fyne.io/fyne/v2/canvas.NewText
      32MB  6.98% 71.53%    93.87MB 20.47%  fyne.io/fyne/v2/widget.NewRichTextWithText
      25MB  5.45% 76.98%       25MB  5.45%  fyne.io/fyne/v2/canvas.NewRectangle (inline)
   22.50MB  4.91% 81.89%    43.71MB  9.53%  fyne.io/fyne/v2/widget.(*RichText).updateRowBounds.func1
   21.81MB  4.76% 86.65%   370.87MB 80.86%  fyne.io/fyne/v2/internal/cache.Renderer
   10.50MB  2.29% 88.94%   250.69MB 54.66%  fyne.io/fyne/v2/widget.(*RichText).CreateRenderer
    9.38MB  2.05% 90.98%     9.38MB  2.05%  github.com/go-text/typesetting/opentype/loader.(*Loader).findTableBuffer
       6MB  1.31% 92.29%        6MB  1.31%  fyne.io/fyne/v2/widget.splitLines
    5.50MB  1.20% 93.49%   181.54MB 39.58%  fyne.io/fyne/v2/widget.(*textRenderer).Refresh
    4.50MB  0.98% 94.47%     4.50MB  0.98%  fyne.io/fyne/v2/internal/cache.(*expiringCache).setAlive
       4MB  0.87% 95.34%        4MB  0.87%  fyne.io/fyne/v2/theme.darkPaletColorNamed
       3MB  0.65% 96.00%     4.50MB  0.98%  github.com/go-text/typesetting/harfbuzz.NewFont
    0.50MB  0.11% 96.11%     8.02MB  1.75%  fyne.io/fyne/v2/internal/driver/glfw.(*gLDriver).startDrawThread.func1
         0     0% 96.11%    15.21MB  3.32%  fyne.io/fyne/v2.MeasureText
         0     0% 96.11%    13.52MB  2.95%  fyne.io/fyne/v2/internal/driver.WalkVisibleObjectTree
         0     0% 96.11%    13.52MB  2.95%  fyne.io/fyne/v2/internal/driver.walkObjectTree
         0     0% 96.11%    13.52MB  2.95%  fyne.io/fyne/v2/internal/driver.walkObjectTree.func1 (inline)
(pprof)
PS C:\Users\ZSA> tasklist /FI "PID eq 11876"

映像名称                       PID 会话名              会话#       内存使用
========================= ======== ================ =========== ============
___6go_build_test.exe        11876 Console                    1  1,009,812 K

3. 10 hours after, the memory usage increased from 155,352 K to 1,009,812 K.

testing code

main.go

main.go
package main
import (
    "fmt"
    "fyne.io/fyne/v2"
    "fyne.io/fyne/v2/app"
    "strconv"
    "time"
)
var rows = [][]string{}
func main() {
    myApp := app.New()
    myWindow := myApp.NewWindow("test")
    myWindow.Resize(fyne.NewSize(1000, 500))
    headers := []string{}
    for i := 0; i < 100; i++ {
       rows = append(rows, make([]string, 100))
       headers = append(headers, "#"+strconv.Itoa(i))
       for j := 0; j < 100; j++ {
          rows[i][j] = fmt.Sprintf("%d:%d", i, j)
       }
    }
    table := NewTableEx(headers)
    myWindow.SetContent(table)
    go runPprof()
    go refreshLoop(table)
    myWindow.ShowAndRun()
}
func refreshLoop(table *TableEx) {
    tick := time.NewTicker(time.Millisecond * 500)
    defer tick.Stop()
    for _ = range tick.C {
       for i := 0; i < 100; i++ {
          for j := 0; j < 100; j++ {
             rows[i][j] = fmt.Sprintf("%d:%d", time.Now().Second()+i, time.Now().Second()+j)
          }
       }
       table.SetMatrix(rows)
    }
}

table.go

package main
import (
    "fyne.io/fyne/v2"
    "fyne.io/fyne/v2/widget"
    "strconv"
    "sync/atomic"
)
type TableEx struct {
    *widget.Table
    header atomic.Pointer[[]string]
    rows   atomic.Pointer[[][]string]
}
func (w *TableEx) Resize(size fyne.Size) {
    w.Table.Resize(size)
}
func (w *TableEx) SetMatrix(ss [][]string) {
    w.rows.Store(&ss)
    w.Table.Refresh()
}
func NewTableEx(header []string) *TableEx {
    table := widget.NewTableWithHeaders(nil, nil, nil)
    table.ShowHeaderRow = true
    table.ShowHeaderColumn = true
    var hlp *TableEx
    hlp = &TableEx{
       header: atomic.Pointer[[]string]{},
       rows:   atomic.Pointer[[][]string]{},
       Table:  table,
    }
    hlp.header.Store(&header)
    hlp.rows.Store(&[][]string{})
    table.Length = func() (rows int, cols int) {
       return len(*hlp.rows.Load()), len(*hlp.header.Load())
    }
    table.CreateCell = func() fyne.CanvasObject {
       return widget.NewLabelWithStyle("", fyne.TextAlignCenter, fyne.TextStyle{})
    }
    table.CreateHeader = func() fyne.CanvasObject {
       return widget.NewLabelWithStyle("", fyne.TextAlignCenter, fyne.TextStyle{
          Bold: true,
       })
    }
    table.UpdateCell = func(id widget.TableCellID, template fyne.CanvasObject) {
       l := template.(*widget.Label)
       var text string
       rows := *hlp.rows.Load()
       if id.Row < len(rows) && len(rows[id.Row]) > id.Col {
          text = rows[id.Row][id.Col]
       }
       l.SetText(text)
    }
    table.UpdateHeader = func(id widget.TableCellID, template fyne.CanvasObject) {
       l := template.(*widget.Label)
       if id.Row < 0 {
          h := *hlp.header.Load()
          if id.Col >= len(h) {
          } else {
             l.SetText(h[id.Col])
          }
       } else if id.Col < 0 {
          l.SetText(strconv.Itoa(id.Row + 1))
          if l.Alignment != fyne.TextAlignTrailing {
             l.Alignment = fyne.TextAlignTrailing
          }
       } else {
          return
       }
    }
    return hlp
}

debug.go

package main
import (
	"net/http"
	"net/http/pprof"
)
func runPprof() {
	//http.HandleFunc("/debug/pprof/", pprof.Index)
	//http.HandleFunc("/debug/pprof/cmdline", pprof.Cmdline)
	//http.HandleFunc("/debug/pprof/profile", pprof.Profile)
	//http.HandleFunc("/debug/pprof/symbol", pprof.Symbol)
	//http.HandleFunc("/debug/pprof/trace", pprof.Trace)
	http.HandleFunc("/debug/pprof/allocs", pprof.Handler("allocs").ServeHTTP)
	http.HandleFunc("/debug/pprof/block", pprof.Handler("block").ServeHTTP)
	http.HandleFunc("/debug/pprof/goroutine", pprof.Handler("goroutine").ServeHTTP)
	http.HandleFunc("/debug/pprof/heap", pprof.Handler("heap").ServeHTTP)
	http.HandleFunc("/debug/pprof/mutex", pprof.Handler("mutex").ServeHTTP)
	http.HandleFunc("/debug/pprof/threadcreate", pprof.Handler("threadcreate").ServeHTTP)
	http.ListenAndServe("0.0.0.0:9996", nil)
}

from fyne.

• After 18 hours.
  

from fyne.

If there is indeed a leak, I imagine it must be in GPU textures, as I'm less familiar with how that part of the codebase works and I'm pretty sure there's no leak on the widget/renderer side of things and awhile back did a bit of a codebase audit looking for leaks, fixed a few, but didn't find any in this area.

Or else it's Go holding on to memory because the OS isn't under memory pressure and asking for it back. AFAIK, the Go runtime marks freed memory as "unneeded" on most OSes but retains it, or at least a chunk of it, unless the OS asks for it back, to speed future allocations.

from fyne.

Or else it's Go holding on to memory because the OS isn't under memory pressure and asking for it back. AFAIK, the Go runtime marks freed memory as "unneeded" on most OSes but retains it, or at least a chunk of it, unless the OS asks for it back, to speed future allocations.

I’m no pprof magician but it feels like the built-in profiling in Go should report actual me memory usage and not how much it is holding on to? My best bet is that this is an actual leak somewhere.

from fyne.

From what I can see TableEx is not extending correctly.

type TableEx struct {
    *widget.Table

should be:

type TableEx struct {
    widget.Table

and there is no call to ExtendBaseWidget.

If the code will not produce the same leak with the regular widget.Table then I would say this may not be a leak in the toolkit directly.

from fyne.