René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Add `--jsonl` flag to the `profiling.sampling`","articleBody":"# Feature or enhancement\n\n### Proposal:\n\n\nI'm thinking how to make #145464 more managable, and I realized that sole `--jsonl` is actually a good first step.\n\nAdding `--jsonl` does not depend actually on streaming and will be immediately useful anyway.\n\nThe format described in https://github.com/python/cpython/issues/145464 for:\n\n```\n% cat /tmp/hello_world.py\nimport time\nprint(\"Hello, World!\")\ntime.sleep(0.1)\n```\n\ncould be as simple as:\n\n```json\n{\"type\":\"meta\",\"v\":1,\"run_id\":\"ab2e464d9d814af4b653302f03256520\",\"sample_interval_usec\":1000,\"mode\":\"wall\"}\n{\"type\":\"str_def\",\"v\":1,\"run_id\":\"ab2e464d9d814af4b653302f03256520\",\"defs\":[{\"str_id\":1,\"value\":\"\u003cmodule\u003e\"},{\"str_id\":2,\"value\":\"/tmp/hello_world.py\"},{\"str_id\":3,\"value\":\"_run_code\"},{\"str_id\":4,\"value\":\"\u003cfrozen runpy\u003e\"},{\"str_id\":5,\"value\":\"_run_module_as_main\"}]}\n{\"type\":\"frame_def\",\"v\":1,\"run_id\":\"ab2e464d9d814af4b653302f03256520\",\"defs\":[{\"frame_id\":1,\"path_str_id\":2,\"func_str_id\":1,\"line\":3,\"end_line\":3,\"col\":0,\"end_col\":15},{\"frame_id\":2,\"path_str_id\":4,\"func_str_id\":3,\"line\":87,\"end_line\":87,\"col\":4,\"end_col\":27},{\"frame_id\":3,\"path_str_id\":4,\"func_str_id\":5,\"line\":196,\"end_line\":197,\"col\":11,\"end_col\":42}]}\n{\"type\":\"agg\",\"v\":1,\"run_id\":\"ab2e464d9d814af4b653302f03256520\",\"kind\":\"frame\",\"scope\":\"final\",\"samples_total\":105,\"entries\":[{\"frame_id\":1,\"self\":105,\"cumulative\":105},{\"frame_id\":2,\"self\":0,\"cumulative\":105},{\"frame_id\":3,\"self\":0,\"cumulative\":105}]}\n{\"type\":\"end\",\"v\":1,\"run_id\":\"ab2e464d9d814af4b653302f03256520\",\"samples_total\":105}\n```\n\nPlease use `jq .` to format. I omitted \"\\n\"s for brevity.\n\nThat's without full `meta`, without `raw`, `heartbeat`, `stats`, `error`, as well as without `seq` and timestamps, nor `thread_id`.\n\nWhat's the minimum viable format here? Perhaps it could be marked even as `\"v\":0` while it's polished?\n\n## Open Question\n\nThe format builds on the existing `profiling.sampling` internals.\n\nThere's a very interesting question what should be the first class objects / semantics of the format?\n\nMy honest feeling is that `frame_def` does not really describe frames but places in the code. pprof itself seems to operate more on `location_def` level.\n\nI don't know the previous conversations to make an informed decision here. `frame_def` is much more simpler.\n\nPerhaps there's a more complex discussion to be held? I'm open to any suggestions. \n\nRunning a much deeper comparison between various formats might be warranted.\n\n### Has this already been discussed elsewhere?\n\nhttps://github.com/python/cpython/issues/145464\n\n### Links to previous discussion of this feature:\n\n_No response_\n\n\u003c!-- gh-linked-prs --\u003e\n### Linked PRs\n* gh-146257\n\u003c!-- /gh-linked-prs --\u003e\n","author":{"url":"https://github.com/maurycy","@type":"Person","name":"maurycy"},"datePublished":"2026-03-21T15:57:27.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":2},"url":"https://github.com/146256/cpython/issues/146256"}