Sentry: l0_sublevels.go:658: addFileToSublevels found existing newer file (1) attached stack trace -- stack trace: | runtime.gopanic | GOROOT/src/runtime/panic.go:791 | [...repeated from belo...

This issue was auto filed by Sentry. It represents a crash or reported error on a live cluster with telemetry enabled.

Sentry Link: [https://cockroach-labs.sentry.io/issues/7369550579/?referrer=webhooks_plugin](https://cockroach-labs.sentry.io/issues/7369550579/?referrer=webhooks_plugin)

Panic Message:

```
l0_sublevels.go:658: addFileToSublevels found existing newer file
(1) attached stack trace
-- stack trace:
| runtime.gopanic
| GOROOT/src/runtime/panic.go:791
| [...repeated from below...]
Wraps: (2) assertion failure
Wraps: (3) attached stack trace
-- stack trace:
| github.com/cockroachdb/pebble/internal/manifest.(*l0Sublevels).addFileToSublevels
| external/com_github_cockroachdb_pebble/internal/manifest/l0_sublevels.go:658
| github.com/cockroachdb/pebble/internal/manifest.newL0Sublevels
| external/com_github_cockroachdb_pebble/internal/manifest/l0_sublevels.go:301
| github.com/cockroachdb/pebble/internal/manifest.(*L0Organizer).ResetForTesting
| external/com_github_cockroachdb_pebble/internal/manifest/l0_sublevels.go:2188
| github.com/cockroachdb/pebble/internal/manifest.NewVersionForTesting
| external/com_github_cockroachdb_pebble/internal/manifest/version.go:107
| github.com/cockroachdb/pebble/tool.(*lsmT).buildEdits
| external/com_github_cockroachdb_pebble/tool/lsm.go:326
| github.com/cockroachdb/pebble/tool.(*lsmT).runLSM
| external/com_github_cockroachdb_pebble/tool/lsm.go:160
| github.com/cockroachdb/cockroach/pkg/server/debug.analyzeLSM
| pkg/server/debug/server.go:219
| github.com/cockroachdb/cockroach/pkg/server/debug.(*Server).RegisterEngines.func2
| pkg/server/debug/server.go:276
| net/http.HandlerFunc.ServeHTTP
| GOROOT/src/net/http/server.go:2220
| github.com/cockroachdb/cockroach/pkg/server/debug.(*Server).ServeHTTP
| pkg/server/debug/server.go:309
| github.com/cockroachdb/cockroach/pkg/server.(*httpServer).setupRoutes.makeAdminAuthzCheckHandler.func2
| pkg/server/server_http.go:290
| net/http.HandlerFunc.ServeHTTP
| GOROOT/src/net/http/server.go:2220
| github.com/cockroachdb/cockroach/pkg/server/authserver.(*authenticationMux).ServeHTTP
| pkg/server/authserver/authentication.go:784
| net/http.(*ServeMux).ServeHTTP
| GOROOT/src/net/http/server.go:2747
| net/http.HandlerFunc.ServeHTTP
| GOROOT/src/net/http/server.go:2220
| github.com/NYTimes/gziphandler.NewGzipLevelAndMinSize.func1.1
| external/com_github_nytimes_gziphandler/gzip.go:253
| net/http.HandlerFunc.ServeHTTP
| GOROOT/src/net/http/server.go:2220
| github.com/cockroachdb/cockroach/pkg/server.(*nodeProxy).nodeProxyHandler
| pkg/server/node_http_router.go:58
| github.com/cockroachdb/cockroach/pkg/server.(*httpServer).baseHandler
| pkg/server/server_http.go:425
| github.com/cockroachdb/cockroach/pkg/server.(*serverController).httpMux
| pkg/server/server_controller_http.go:153
| net/http.HandlerFunc.ServeHTTP
| GOROOT/src/net/http/server.go:2220
| net/http.serverHandler.ServeHTTP
| GOROOT/src/net/http/server.go:3210
| net/http.(*conn).serve
| GOROOT/src/net/http/server.go:2092
| runtime.goexit
| src/runtime/asm_amd64.s:1700
Wraps: (4) addFileToSublevels found existing newer file
Error types: (1) *withstack.withStack (2) *assert.withAssertionFailure (3) *withstack.withStack (4) *errutil.leafError
-- report composition:
*errutil.leafError: addFileToSublevels found existing newer file
l0_sublevels.go:658: *withstack.withStack (top exception)
*assert.withAssertionFailure
panic.go:791: *withstack.withStack (1)
(check the extra data payloads)
```

Stacktrace (expand for inline code snippets):

[src/runtime/asm_amd64.s#L1699-L1701](src/runtime/asm_amd64.s#L1699-L1701)
[GOROOT/src/net/http/server.go#L2091-L2093](GOROOT/src/net/http/server.go#L2091-L2093)
[GOROOT/src/net/http/server.go#L3209-L3211](GOROOT/src/net/http/server.go#L3209-L3211)
[GOROOT/src/net/http/server.go#L2219-L2221](GOROOT/src/net/http/server.go#L2219-L2221)
[pkg/server/server_controller_http.go#L152-L154](pkg/server/server_controller_http.go#L152-L154)
[pkg/server/server_http.go#L424-L426](pkg/server/server_http.go#L424-L426)
[pkg/server/node_http_router.go#L57-L59](pkg/server/node_http_router.go#L57-L59)
[GOROOT/src/net/http/server.go#L2219-L2221](GOROOT/src/net/http/server.go#L2219-L2221)
[external/com_github_nytimes_gziphandler/gzip.go#L252-L254](external/com_github_nytimes_gziphandler/gzip.go#L252-L254)
[GOROOT/src/net/http/server.go#L2219-L2221](GOROOT/src/net/http/server.go#L2219-L2221)
[GOROOT/src/net/http/server.go#L2746-L2748](GOROOT/src/net/http/server.go#L2746-L2748)
[pkg/server/authserver/authentication.go#L783-L785](pkg/server/authserver/authentication.go#L783-L785)
[GOROOT/src/net/http/server.go#L2219-L2221](GOROOT/src/net/http/server.go#L2219-L2221)
[pkg/server/server_http.go#L289-L291](pkg/server/server_http.go#L289-L291)
[pkg/server/debug/server.go#L308-L310](pkg/server/debug/server.go#L308-L310)
[GOROOT/src/net/http/server.go#L2219-L2221](GOROOT/src/net/http/server.go#L2219-L2221)
[pkg/server/debug/server.go#L275-L277](pkg/server/debug/server.go#L275-L277)
[pkg/server/debug/server.go#L218-L220](pkg/server/debug/server.go#L218-L220)
[external/com_github_cockroachdb_pebble/tool/lsm.go#L159-L161](external/com_github_cockroachdb_pebble/tool/lsm.go#L159-L161)
[external/com_github_cockroachdb_pebble/tool/lsm.go#L325-L327](external/com_github_cockroachdb_pebble/tool/lsm.go#L325-L327)
[external/com_github_cockroachdb_pebble/internal/manifest/version.go#L106-L108](external/com_github_cockroachdb_pebble/internal/manifest/version.go#L106-L108)
[external/com_github_cockroachdb_pebble/internal/manifest/l0_sublevels.go#L2187-L2189](external/com_github_cockroachdb_pebble/internal/manifest/l0_sublevels.go#L2187-L2189)
[external/com_github_cockroachdb_pebble/internal/manifest/l0_sublevels.go#L300-L302](external/com_github_cockroachdb_pebble/internal/manifest/l0_sublevels.go#L300-L302)
[external/com_github_cockroachdb_pebble/internal/manifest/l0_sublevels.go#L657-L659](external/com_github_cockroachdb_pebble/internal/manifest/l0_sublevels.go#L657-L659)
[GOROOT/src/runtime/panic.go#L790-L792](GOROOT/src/runtime/panic.go#L790-L792)
[src/runtime/asm_amd64.s#L1699-L1701](src/runtime/asm_amd64.s#L1699-L1701)
[GOROOT/src/net/http/server.go#L2091-L2093](GOROOT/src/net/http/server.go#L2091-L2093)
[GOROOT/src/net/http/server.go#L3209-L3211](GOROOT/src/net/http/server.go#L3209-L3211)
[GOROOT/src/net/http/server.go#L2219-L2221](GOROOT/src/net/http/server.go#L2219-L2221)
[pkg/server/server_controller_http.go#L152-L154](pkg/server/server_controller_http.go#L152-L154)
[pkg/server/server_http.go#L424-L426](pkg/server/server_http.go#L424-L426)
[pkg/server/node_http_router.go#L57-L59](pkg/server/node_http_router.go#L57-L59)
[GOROOT/src/net/http/server.go#L2219-L2221](GOROOT/src/net/http/server.go#L2219-L2221)
[external/com_github_nytimes_gziphandler/gzip.go#L252-L254](external/com_github_nytimes_gziphandler/gzip.go#L252-L254)
[GOROOT/src/net/http/server.go#L2219-L2221](GOROOT/src/net/http/server.go#L2219-L2221)
[GOROOT/src/net/http/server.go#L2746-L2748](GOROOT/src/net/http/server.go#L2746-L2748)
[pkg/server/authserver/authentication.go#L783-L785](pkg/server/authserver/authentication.go#L783-L785)
[GOROOT/src/net/http/server.go#L2219-L2221](GOROOT/src/net/http/server.go#L2219-L2221)
[pkg/server/server_http.go#L289-L291](pkg/server/server_http.go#L289-L291)
[pkg/server/debug/server.go#L308-L310](pkg/server/debug/server.go#L308-L310)
[GOROOT/src/net/http/server.go#L2219-L2221](GOROOT/src/net/http/server.go#L2219-L2221)
[pkg/server/debug/server.go#L275-L277](pkg/server/debug/server.go#L275-L277)
[pkg/server/debug/server.go#L218-L220](pkg/server/debug/server.go#L218-L220)
[external/com_github_cockroachdb_pebble/tool/lsm.go#L159-L161](external/com_github_cockroachdb_pebble/tool/lsm.go#L159-L161)
[external/com_github_cockroachdb_pebble/tool/lsm.go#L325-L327](external/com_github_cockroachdb_pebble/tool/lsm.go#L325-L327)
[external/com_github_cockroachdb_pebble/internal/manifest/version.go#L106-L108](external/com_github_cockroachdb_pebble/internal/manifest/version.go#L106-L108)
[external/com_github_cockroachdb_pebble/internal/manifest/l0_sublevels.go#L2187-L2189](external/com_github_cockroachdb_pebble/internal/manifest/l0_sublevels.go#L2187-L2189)
[external/com_github_cockroachdb_pebble/internal/manifest/l0_sublevels.go#L300-L302](external/com_github_cockroachdb_pebble/internal/manifest/l0_sublevels.go#L300-L302)
[external/com_github_cockroachdb_pebble/internal/manifest/l0_sublevels.go#L657-L659](external/com_github_cockroachdb_pebble/internal/manifest/l0_sublevels.go#L657-L659)

```
src/runtime/asm_amd64.s in runtime.goexit at line 1700
GOROOT/src/net/http/server.go in net/http.(*conn).serve at line 2092
GOROOT/src/net/http/server.go in net/http.serverHandler.ServeHTTP at line 3210
GOROOT/src/net/http/server.go in net/http.HandlerFunc.ServeHTTP at line 2220
pkg/server/server_controller_http.go in pkg/server.(*serverController).httpMux at line 153
pkg/server/server_http.go in pkg/server.(*httpServer).baseHandler at line 425
pkg/server/node_http_router.go in pkg/server.(*nodeProxy).nodeProxyHandler at line 58
GOROOT/src/net/http/server.go in net/http.HandlerFunc.ServeHTTP at line 2220
external/com_github_nytimes_gziphandler/gzip.go in github.com/NYTimes/gziphandler.NewGzipLevelAndMinSize.func1.1 at line 253
GOROOT/src/net/http/server.go in net/http.HandlerFunc.ServeHTTP at line 2220
GOROOT/src/net/http/server.go in net/http.(*ServeMux).ServeHTTP at line 2747
pkg/server/authserver/authentication.go in pkg/server/authserver.(*authenticationMux).ServeHTTP at line 784
GOROOT/src/net/http/server.go in net/http.HandlerFunc.ServeHTTP at line 2220
pkg/server/server_http.go in pkg/server.(*httpServer).setupRoutes.makeAdminAuthzCheckHandler.func2 at line 290
pkg/server/debug/server.go in pkg/server/debug.(*Server).ServeHTTP at line 309
GOROOT/src/net/http/server.go in net/http.HandlerFunc.ServeHTTP at line 2220
pkg/server/debug/server.go in pkg/server/debug.(*Server).RegisterEngines.func2 at line 276
pkg/server/debug/server.go in pkg/server/debug.analyzeLSM at line 219
external/com_github_cockroachdb_pebble/tool/lsm.go in github.com/cockroachdb/pebble/tool.(*lsmT).runLSM at line 160
external/com_github_cockroachdb_pebble/tool/lsm.go in github.com/cockroachdb/pebble/tool.(*lsmT).buildEdits at line 326
external/com_github_cockroachdb_pebble/internal/manifest/version.go in github.com/cockroachdb/pebble/internal/manifest.NewVersionForTesting at line 107
external/com_github_cockroachdb_pebble/internal/manifest/l0_sublevels.go in github.com/cockroachdb/pebble/internal/manifest.(*L0Organizer).ResetForTesting at line 2188
external/com_github_cockroachdb_pebble/internal/manifest/l0_sublevels.go in github.com/cockroachdb/pebble/internal/manifest.newL0Sublevels at line 301
external/com_github_cockroachdb_pebble/internal/manifest/l0_sublevels.go in github.com/cockroachdb/pebble/internal/manifest.(*l0Sublevels).addFileToSublevels at line 658
GOROOT/src/runtime/panic.go in runtime.gopanic at line 791
src/runtime/asm_amd64.s in runtime.goexit at line 1700
GOROOT/src/net/http/server.go in net/http.(*conn).serve at line 2092
GOROOT/src/net/http/server.go in net/http.serverHandler.ServeHTTP at line 3210
GOROOT/src/net/http/server.go in net/http.HandlerFunc.ServeHTTP at line 2220
pkg/server/server_controller_http.go in pkg/server.(*serverController).httpMux at line 153
pkg/server/server_http.go in pkg/server.(*httpServer).baseHandler at line 425
pkg/server/node_http_router.go in pkg/server.(*nodeProxy).nodeProxyHandler at line 58
GOROOT/src/net/http/server.go in net/http.HandlerFunc.ServeHTTP at line 2220
external/com_github_nytimes_gziphandler/gzip.go in github.com/NYTimes/gziphandler.NewGzipLevelAndMinSize.func1.1 at line 253
GOROOT/src/net/http/server.go in net/http.HandlerFunc.ServeHTTP at line 2220
GOROOT/src/net/http/server.go in net/http.(*ServeMux).ServeHTTP at line 2747
pkg/server/authserver/authentication.go in pkg/server/authserver.(*authenticationMux).ServeHTTP at line 784
GOROOT/src/net/http/server.go in net/http.HandlerFunc.ServeHTTP at line 2220
pkg/server/server_http.go in pkg/server.(*httpServer).setupRoutes.makeAdminAuthzCheckHandler.func2 at line 290
pkg/server/debug/server.go in pkg/server/debug.(*Server).ServeHTTP at line 309
GOROOT/src/net/http/server.go in net/http.HandlerFunc.ServeHTTP at line 2220
pkg/server/debug/server.go in pkg/server/debug.(*Server).RegisterEngines.func2 at line 276
pkg/server/debug/server.go in pkg/server/debug.analyzeLSM at line 219
external/com_github_cockroachdb_pebble/tool/lsm.go in github.com/cockroachdb/pebble/tool.(*lsmT).runLSM at line 160
external/com_github_cockroachdb_pebble/tool/lsm.go in github.com/cockroachdb/pebble/tool.(*lsmT).buildEdits at line 326
external/com_github_cockroachdb_pebble/internal/manifest/version.go in github.com/cockroachdb/pebble/internal/manifest.NewVersionForTesting at line 107
external/com_github_cockroachdb_pebble/internal/manifest/l0_sublevels.go in github.com/cockroachdb/pebble/internal/manifest.(*L0Organizer).ResetForTesting at line 2188
external/com_github_cockroachdb_pebble/internal/manifest/l0_sublevels.go in github.com/cockroachdb/pebble/internal/manifest.newL0Sublevels at line 301
external/com_github_cockroachdb_pebble/internal/manifest/l0_sublevels.go in github.com/cockroachdb/pebble/internal/manifest.(*l0Sublevels).addFileToSublevels at line 658
```

### Tags

| Tag | Value |
| --- | --- |
| Command | server |
| Environment | v25.4.3 |
| Go Version | go1.23.12 X:nocoverageredesign |
| Platform | linux amd64 |
| Distribution | CCL |
| Cockroach Release | v25.4.3 |
| Cockroach SHA | 71d853623f0d1f589fd5c727a1c4aec8a43e62e0 |
| # of CPUs | 8 |
| # of Goroutines | 1747 |

Jira issue: CRDB-62172