From c40e21225f11905954249dc2ce305bcb3ef2da31 Mon Sep 17 00:00:00 2001 From: inventarSarah Date: Wed, 17 Jun 2026 10:48:56 +0200 Subject: [PATCH 1/6] draft New Spans and Migration Guide pages --- .../python/tracing/new-spans/index.mdx | 408 ++++++++++++++++++ .../tracing/new-spans/migration-guide.mdx | 240 +++++++++++ 2 files changed, 648 insertions(+) create mode 100644 docs/platforms/python/tracing/new-spans/index.mdx create mode 100644 docs/platforms/python/tracing/new-spans/migration-guide.mdx diff --git a/docs/platforms/python/tracing/new-spans/index.mdx b/docs/platforms/python/tracing/new-spans/index.mdx new file mode 100644 index 0000000000000..4e043c7b8d844 --- /dev/null +++ b/docs/platforms/python/tracing/new-spans/index.mdx @@ -0,0 +1,408 @@ +--- +title: New Spans +description: "Learn how to use stream mode to send spans to Sentry as they finish, removing the 1,000-span limit and making trace data visible sooner." +sidebar_order: 45 +new: true +--- + +By default, the Sentry Python SDK collects all spans in memory and sends them to Sentry as a single transaction once the root span ends. This is called transaction mode. +Stream mode changes this by sending spans to Sentry in batches as they finish. Service spans, which represent a service's entry point, replace transactions as the main grouping for each service. + + + +- **No 1,000-span limit.** In transaction mode, transactions are capped at 1,000 spans. Stream mode has no upper limit since spans are sent in batches. +- **Lower memory usage.** Spans are flushed periodically and don't need to be held in memory until the root span ends. This is especially useful for long-running processes like queue consumers or cron jobs. +- **Faster visibility.** Span data arrives in Sentry as your application runs, instead of only after the entire operation completes. +- **No data loss from crashes.** If your process terminates unexpectedly, spans that were already flushed are preserved. In transaction mode, a crash before the root span ends means all span data is lost. + + + +You can find the following span types mentioned throughout this page: + +- **Root span**: The topmost span in a trace. It has no parent span and is always a service span. +- **Service span**: A parent-level span at the entry of a service. In transaction mode, this is called a transaction. +- **Child span**: Any span nested under a parent span within the same trace. + +This graph shows how these span types relate to each other within a trace: + +``` +Trace +│ +└── Root span [service A] + ├── Child span + │ └── Child span + └── Service span [service B] + ├── Child span + └── Child span +``` + + + +Stream mode requires the new Span API, so migrating to stream mode and migrating to the new Span API are the same step. If you have existing custom instrumentation, see the Migration Guide for a full list of changes. + + + +## Prerequisites + +You need: + +- Tracing configured in + your app +- Sentry SDK `>=2.62.0` + +## Enable Stream Mode + + + + + +Opt in by adding `trace_lifecycle` to the `_experiments` option when initializing the SDK: + + + + +```python +import sentry_sdk + +sentry_sdk.init( + dsn="___PUBLIC_DSN___", + traces_sample_rate=1.0, + _experiments={ + # enables stream mode + "trace_lifecycle": "stream", + }, +) + +``` + + + + + +To revert to transaction mode, remove the `_experiments` option or set `trace_lifecycle` to `"static"` (the default). + + + +When stream mode is enabled, the SDK maintains an internal buffer that groups spans by trace ID. + +Spans are flushed: + +- On a regular interval (every 5 seconds by default). +- When a trace's buffer reaches 1,000 spans. +- When the SDK shuts down. + +Each flush sends only the spans accumulated since the last flush, grouped into envelopes by trace ID. + + + +## Manual Instrumenation (Optional) + +### Start a Span + + + + + +Use `sentry_sdk.traces.start_span()` to create a span that ends automatically when the `with` block exits: + + + + +```python +import sentry_sdk + +with sentry_sdk.traces.start_span(name="my-operation") as span: + # Your code here + do_work() +``` + + + + + + +Child spans created inside an active span are automatically associated with the parent: + + + + +```python +import sentry_sdk + +with sentry_sdk.traces.start_span(name="parent-operation"): + with sentry_sdk.traces.start_span(name="child-step-1"): + step_one() + + with sentry_sdk.traces.start_span(name="child-step-2"): + step_two() +``` + + + + + + +To start a service span (the equivalent of a transaction), set `parent_span=None`: + + + + +```python +import sentry_sdk + +with sentry_sdk.traces.start_span(name="task-name", parent_span=None) as span: + do_work() +``` + + + + + + +You can also use the `@trace` decorator to instrument a function. It accepts optional `name`, `attributes`, and `active` arguments: + + + + +```python +from sentry_sdk.traces import trace + +@trace(name="checkout", attributes={"flow.pipeline": "legacy"}) +def checkout(): + ... +``` + + + + + +For more details on span creation, see Custom Instrumentation. + +### Add Span Attributes + +Attach structured metadata to spans using `attributes`, which can be `str`, `int`, `float`, or `bool`, as well as arrays of these types. + + + + + +You can set attributes when starting a span: + + + + +```python +import sentry_sdk + +with sentry_sdk.traces.start_span( + name="process-order", + attributes={ + "sentry.op": "queue.process", + "order.id": "abc-123", + "order.item_count": 5, + "order.priority": True, + }, +): + process_order() +``` + + + + + + + +Or add them to an already running span: + + + + +```python +import sentry_sdk + +with sentry_sdk.traces.start_span(name="handle-request") as span: + # Set a single attribute + span.set_attribute("http.response.status_code", 200) + + # Set multiple attributes at once + span.set_attributes({ + "http.route": "/api/users", + "user.id": "user-42", + }) +``` + + + + + +Find more examples in our Sending Span Metrics documentation. + +## Distributed Tracing (Optional) + +### Continue a Trace + + + + + +When your service receives a request from an upstream service that includes Sentry trace headers, use `sentry_sdk.traces.continue_trace()` to connect your spans to the existing distributed trace. +Unlike the legacy `sentry_sdk.continue_trace()`, the new version is not a context manager. Instead, it sets the propagation context and the next span picks it up automatically. + + + + +```python +import sentry_sdk + +headers = { + "sentry-trace": "4bf92f3577b34da6a3ce929d0e0e4736-00f067aa0be902b7-1", + "baggage": "sentry-trace_id=...", +} + +sentry_sdk.traces.continue_trace(headers) +with sentry_sdk.traces.start_span(name="handle request"): + ... +``` + + + + + +### Start a New Trace + + + + + +If you need to start a completely new trace unconnected to the current one, use `sentry_sdk.traces.new_trace()`. This is useful for background jobs or scheduled tasks where you want a clean trace boundary: + + + + +```python +import sentry_sdk + +with sentry_sdk.traces.start_span(name="span in trace 1"): + ... + +sentry_sdk.traces.new_trace() + +with sentry_sdk.traces.start_span(name="span in trace 2"): + # This span is the root of a new, separate trace + ... +``` + + + + + +See Custom Trace Propagation for more information on distributed tracing. + +## Extended Configuration (Optional) + +### Filter Spans + + + + + +To modify or redact span data before it's sent, use `before_send_span` in the `_experiments` option: + + + + +```python +import sentry_sdk + +def postprocess_span(span, hint): + attributes_to_sanitize = [ + "http.request.header.custom-auth", + "http.request.header.custom-user-id", + ] + for attribute in attributes_to_sanitize: + if span["attributes"].get(attribute): + span["attributes"][attribute] = "[Sanitized]" + return span + +sentry_sdk.init( + dsn="___PUBLIC_DSN___", + traces_sample_rate=1.0, + _experiments={ + "trace_lifecycle": "stream", + "before_send_span": postprocess_span, + }, +) +``` + + + + + + + +`before_send_span` can only modify span data — you cannot use it to drop spans (use [`ignore_spans`](#drop-spans) instead), and it can only work with attributes set at span start time. Attributes added later during the span's lifetime are not available. + + + +### Drop Spans + + + + + +To prevent specific spans from being created, use `ignore_spans` in the `_experiments` option. Rules are evaluated at span start, so only the span name and attributes set at creation time are taken into account. Rules can be strings, compiled regexes, or dictionaries with name and/or attributes conditions: + + + + +```python +import re +import sentry_sdk + +sentry_sdk.init( + dsn="___PUBLIC_DSN___", + traces_sample_rate=1.0, + _experiments={ + "trace_lifecycle": "stream", + "ignore_spans": [ + # String match against span name + "/health", + # Regex match against span name + re.compile(r"/flow/.*"), + # Match by attributes (all must match) + { + "attributes": { + "service.id": "15def9a", + "flow.pipeline": "legacy", + } + }, + # Match by name and attributes + { + "name": re.compile(r"/flow/.*"), + "attributes": { + "service.id": re.compile(r".*\.facade"), + }, + }, + ], + }, +) +``` + + + + + +If a matching span is a service span, all of its child spans are dropped as well. If a child span matches, only that span is dropped and its children are reparented to the nearest ancestor. + +## Sampling (Optional) + +If you use `traces_sample_rate`, no changes are needed — it works the same way in stream mode. + +If you use a custom `traces_sampler`, the shape of the sampling context is different in stream mode. See the New Span API migration guide for details. + +## Verify Your Setup + +To make sure you've enabled stream mode successfully: + +- **Check the Sentry dashboard**: Spans should appear in the Traces view shortly after they complete. Traces look similar to transaction mode, but contain only spans and no transactions. +- **Check your logs**: If the SDK logs warnings about unsupported span operations, you may still be using the legacy Span API somewhere in your code. diff --git a/docs/platforms/python/tracing/new-spans/migration-guide.mdx b/docs/platforms/python/tracing/new-spans/migration-guide.mdx new file mode 100644 index 0000000000000..b6f1f567d7415 --- /dev/null +++ b/docs/platforms/python/tracing/new-spans/migration-guide.mdx @@ -0,0 +1,240 @@ +--- +title: Migrate to Stream Mode +sidebar_order: 10 +description: "Learn how to migrate your custom instrumentation from transaction mode to stream mode." +--- + +Stream mode requires the new Span API. If you use custom instrumentation (creating spans manually, setting span data, or filtering spans) you'll need to update that code before you can switch to stream mode. This guide walks through the changes. + +For an introduction to stream mode itself, see New Spans. + +## Enable Stream Mode + +Add `trace_lifecycle` to the `_experiments` option when initializing the SDK: + +```python diff +import sentry_sdk + +sentry_sdk.init( + dsn="___PUBLIC_DSN___", + traces_sample_rate=1.0, ++ _experiments={ ++ "trace_lifecycle": "stream", ++ }, +) +``` + +## Span Creation + +Replace `start_span`, `start_transaction`, and `start_child` with `sentry_sdk.traces.start_span()`. Whether the resulting span is a service span, a child span, or a sibling depends on the `parent_span` argument and what's currently active. + +```python diff +import sentry_sdk + +# Starting a span +- with sentry_sdk.start_span(op="http.client", description="GET /api/users") as span: ++ with sentry_sdk.traces.start_span( ++ name="GET /api/users", ++ attributes={"sentry.op": "http.client"}, ++ ) as span: + ... + +# Starting what used to be a transaction: pass parent_span=None to force a service span +- with sentry_sdk.start_transaction(name="flow.checkout") as transaction: ++ with sentry_sdk.traces.start_span(name="flow.checkout", parent_span=None) as span: + ... + +# Starting a child span: just start a span while the parent is active +- with parent.start_child(op="db", description="SELECT") as child: ++ with sentry_sdk.traces.start_span(name="SELECT", attributes={"sentry.op": "db"}): + ... +``` + +A few argument changes come along with this: + +- `description` no longer exists — use `name` instead. +- `op` is no longer a dedicated argument — set it as the `sentry.op` attribute instead. + +If you use the `@trace` decorator, only the import changes: + +```python diff +- from sentry_sdk import trace ++ from sentry_sdk.traces import trace + +@trace +def checkout(): + ... +``` + +If your code imports `Span` or `Transaction` directly, for example for type annotations, replace both with `StreamedSpan`: + +```python diff +- from sentry_sdk.tracing import Span, Transaction ++ from sentry_sdk.traces import StreamedSpan + +- def process(span: Span) -> None: ++ def process(span: StreamedSpan) -> None: + ... +``` + +## Span Data + +In stream mode, spans have no contexts, data, or tags. Instead, everything is an attribute. +Replace `set_data()`, `set_tag()`, and `set_context()` with `set_attribute()` or `set_attributes()`: + +```python diff +- span.set_data("flow.step", "submit_payment") +- span.set_tag("http.status_code", 201) ++ span.set_attributes({ ++ "flow.step": "submit_payment", ++ "http.response.status_code": 201, ++ }) +``` + +Unlike the old methods, `set_attribute` only accepts primitive types (`str`, `int`, `float`, `bool`, or arrays of these). `None` isn't supported either. Flatten dictionaries into separate attributes, and stringify anything that can't be flattened: + +```python diff +- span.set_data("request", {"method": "POST", "path": "/api/checkout"}) ++ span.set_attributes({ ++ "request.method": "POST", ++ "request.path": "/api/checkout", ++ }) +``` + +Tags set on the scope with `sentry_sdk.set_tag()` aren't applied to spans in stream mode. Use `sentry_sdk.set_attribute()` to apply data to spans: + +```python +sentry_sdk.set_tag("region", "Europe") # applied to errors and other tag-supporting telemetry +sentry_sdk.set_attribute("region", "Europe") # applied to spans, logs, metrics +``` + +## Accessing the Current Span + +A few ways of referencing the current span or transaction change in stream mode: + +```python diff +# Getting the current span +- span = sentry_sdk.get_current_span() ++ span = sentry_sdk.traces.get_current_span() + +# Getting the current span via the scope +- scope = sentry_sdk.get_current_scope() +- current_span = scope.span ++ current_span = sentry_sdk.traces.get_current_span() + +# Getting the service span (formerly the transaction) +- scope = sentry_sdk.get_current_scope() +- transaction = scope.transaction ++ service_span = sentry_sdk.traces.get_current_span()._segment + +# Getting the service span from a child span +- transaction = span.containing_transaction ++ service_span = span._segment +``` + +`_segment` returns the service span of the current trace (the equivalent of what used to be the transaction). It is a private API — prefer restructuring the code to avoid needing the service span where possible. + +If your code reads specific fields off the trace context, access them as direct properties instead of calling `get_trace_context()`, which no longer exists on streaming spans: + +```python diff +- ctx = span.get_trace_context() +- trace_id = ctx["trace_id"] +- span_id = ctx["span_id"] ++ trace_id = span.trace_id ++ span_id = span.span_id +``` + +If you genuinely need the full trace context dict, for example to pass it to an external system, use the private `span._get_trace_context()` method instead. Prefer the direct properties where possible. + +## Trace Propagation + +`sentry_sdk.traces.continue_trace()` replaces the legacy `continue_trace()`. It's no longer a context manager — it sets the propagation context, and the next span you start picks it up automatically: + +```python diff +headers = { + "sentry-trace": "...", + "baggage": "...", +} + +- with sentry_sdk.continue_trace(headers) as transaction: +- ... ++ sentry_sdk.traces.continue_trace(headers) ++ with sentry_sdk.traces.start_span(name="handle request"): ++ ... +``` + +## Span Status + +Status can only be `ok` (default) or `error` in stream mode: + +```python +from sentry_sdk.traces import start_span + +with start_span(name="process") as span: + try: + ... + except Exception: + span.status = "error" +``` + +## Sampling + +If you use `traces_sample_rate`, no changes are needed. + +If you use a custom `traces_sampler`, the sampling context has a different structure in stream mode. Span details are available under `sampling_context["span_context"]`, which includes `name`, `trace_id`, `parent_span_id`, `parent_sampled`, and `attributes`: + +```python +def traces_sampler(sampling_context): + if sampling_context["span_context"]["name"] in IGNORED_SPAN_NAMES: + return 0.0 + return 1.0 + +sentry_sdk.init( + traces_sampler=traces_sampler, + _experiments={"trace_lifecycle": "stream"}, +) +``` + +`custom_sampling_context` is no longer an argument to `start_span`. Set it on the scope instead, after `continue_trace` (which resets the propagation context) and before `start_span` (which is when sampling happens): + +```python diff +- with sentry_sdk.start_span( +- name="handle request", +- custom_sampling_context={"asgi_scope": asgi_scope}, +- ): +- ... ++ sentry_sdk.Scope.set_custom_sampling_context({"asgi_scope": asgi_scope}) ++ with sentry_sdk.traces.start_span(name="handle request"): ++ ... +``` + +## Filtering and Dropping Spans + +`before_send_transaction` has no effect in stream mode, since spans are sent individually rather than batched into a transaction. Replace it with `ignore_spans` (to drop spans) and `before_send_span` (to modify them), both configured under `_experiments`: + +```python diff +import re +import sentry_sdk + ++ def my_span_processor(span, hint): ++ if span["attributes"].get("sentry.op") == "db.query": ++ span["name"] = "[filtered]" ++ return span + +sentry_sdk.init( + dsn="___PUBLIC_DSN___", + traces_sample_rate=1.0, +- before_send_transaction=my_filter, ++ _experiments={ ++ "trace_lifecycle": "stream", ++ "ignore_spans": [ ++ "/health", ++ re.compile(r"^GET /api/v1/internal"), ++ {"attributes": {"service.id": "15def9a"}}, ++ ], ++ "before_send_span": my_span_processor, ++ }, +) +``` + +Both `ignore_spans` and `before_send_span` only have access to the span name and attributes set at creation time — not attributes added later in the span's lifetime, like an HTTP status code set after the request completes. If your `before_send_transaction` logic depended on that kind of late-set data, it can't be replicated in stream mode. Consider server-side filtering with Sentry inbound data filters or Relay rules instead. From 2a64622089366ba46a5036fc9225ded43826ecc7 Mon Sep 17 00:00:00 2001 From: inventarSarah Date: Wed, 17 Jun 2026 10:58:42 +0200 Subject: [PATCH 2/6] fix typo --- docs/platforms/python/tracing/new-spans/index.mdx | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/docs/platforms/python/tracing/new-spans/index.mdx b/docs/platforms/python/tracing/new-spans/index.mdx index 4e043c7b8d844..576e2f2b4483b 100644 --- a/docs/platforms/python/tracing/new-spans/index.mdx +++ b/docs/platforms/python/tracing/new-spans/index.mdx @@ -95,7 +95,7 @@ Each flush sends only the spans accumulated since the last flush, grouped into e -## Manual Instrumenation (Optional) +## Manual Instrumentation (Optional) ### Start a Span From 2ef7b0ee26bbed9d3841eeb810a01252db9f036b Mon Sep 17 00:00:00 2001 From: inventarSarah Date: Wed, 17 Jun 2026 11:18:17 +0200 Subject: [PATCH 3/6] fix link --- docs/platforms/python/tracing/new-spans/index.mdx | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/docs/platforms/python/tracing/new-spans/index.mdx b/docs/platforms/python/tracing/new-spans/index.mdx index 576e2f2b4483b..3c75e6973e422 100644 --- a/docs/platforms/python/tracing/new-spans/index.mdx +++ b/docs/platforms/python/tracing/new-spans/index.mdx @@ -398,7 +398,7 @@ If a matching span is a service span, all of its child spans are dropped as well If you use `traces_sample_rate`, no changes are needed — it works the same way in stream mode. -If you use a custom `traces_sampler`, the shape of the sampling context is different in stream mode. See the New Span API migration guide for details. +If you use a custom `traces_sampler`, the shape of the sampling context is different in stream mode. See the New Span API migration guide for details. ## Verify Your Setup From 00be0cec5a4209ff90770dafb669803a33e60ae0 Mon Sep 17 00:00:00 2001 From: inventarSarah Date: Mon, 22 Jun 2026 15:42:26 +0200 Subject: [PATCH 4/6] PR feedback --- docs/platforms/python/tracing/new-spans/index.mdx | 8 +++++++- .../python/tracing/new-spans/migration-guide.mdx | 14 +------------- 2 files changed, 8 insertions(+), 14 deletions(-) diff --git a/docs/platforms/python/tracing/new-spans/index.mdx b/docs/platforms/python/tracing/new-spans/index.mdx index 3c75e6973e422..3084d9d02b8f8 100644 --- a/docs/platforms/python/tracing/new-spans/index.mdx +++ b/docs/platforms/python/tracing/new-spans/index.mdx @@ -10,7 +10,7 @@ Stream mode changes this by sending spans to Sentry in batches as they finish. S -- **No 1,000-span limit.** In transaction mode, transactions are capped at 1,000 spans. Stream mode has no upper limit since spans are sent in batches. +- **No 1,000-span limit.** In transaction mode, transactions are capped at 1,000 spans. Stream mode has no upper limit since spans are sent in batches. This is especially beneficial for complex generative AI pipelines that easily exceed standard span limits. - **Lower memory usage.** Spans are flushed periodically and don't need to be held in memory until the root span ends. This is especially useful for long-running processes like queue consumers or cron jobs. - **Faster visibility.** Span data arrives in Sentry as your application runs, instead of only after the entire operation completes. - **No data loss from crashes.** If your process terminates unexpectedly, spans that were already flushed are preserved. In transaction mode, a crash before the root span ends means all span data is lost. @@ -182,6 +182,12 @@ For more details on span creation, see + +Sentry automatically sets several standard attributes on spans. To avoid accidentally overwriting these, refer to our Sentry Attribute Conventions. + + + diff --git a/docs/platforms/python/tracing/new-spans/migration-guide.mdx b/docs/platforms/python/tracing/new-spans/migration-guide.mdx index b6f1f567d7415..d3e6a3c523b30 100644 --- a/docs/platforms/python/tracing/new-spans/migration-guide.mdx +++ b/docs/platforms/python/tracing/new-spans/migration-guide.mdx @@ -122,18 +122,8 @@ A few ways of referencing the current span or transaction change in stream mode: - current_span = scope.span + current_span = sentry_sdk.traces.get_current_span() -# Getting the service span (formerly the transaction) -- scope = sentry_sdk.get_current_scope() -- transaction = scope.transaction -+ service_span = sentry_sdk.traces.get_current_span()._segment - -# Getting the service span from a child span -- transaction = span.containing_transaction -+ service_span = span._segment ``` -`_segment` returns the service span of the current trace (the equivalent of what used to be the transaction). It is a private API — prefer restructuring the code to avoid needing the service span where possible. - If your code reads specific fields off the trace context, access them as direct properties instead of calling `get_trace_context()`, which no longer exists on streaming spans: ```python diff @@ -144,8 +134,6 @@ If your code reads specific fields off the trace context, access them as direct + span_id = span.span_id ``` -If you genuinely need the full trace context dict, for example to pass it to an external system, use the private `span._get_trace_context()` method instead. Prefer the direct properties where possible. - ## Trace Propagation `sentry_sdk.traces.continue_trace()` replaces the legacy `continue_trace()`. It's no longer a context manager — it sets the propagation context, and the next span you start picks it up automatically: @@ -237,4 +225,4 @@ sentry_sdk.init( ) ``` -Both `ignore_spans` and `before_send_span` only have access to the span name and attributes set at creation time — not attributes added later in the span's lifetime, like an HTTP status code set after the request completes. If your `before_send_transaction` logic depended on that kind of late-set data, it can't be replicated in stream mode. Consider server-side filtering with Sentry inbound data filters or Relay rules instead. +Both `ignore_spans` and `before_send_span` only have access to the span name and attributes set at creation time — not attributes added later in the span's lifetime, like an HTTP status code set after the request completes. If your `before_send_transaction` logic depended on that kind of late-set data, it can't be replicated in stream mode. Consider server-side filtering with Sentry [inbound data filters](/concepts/data-management/filtering/) or [Relay](/product/relay/) rules instead. From 6e754f2848ba926fada1eb76f648335fcaa8a8a1 Mon Sep 17 00:00:00 2001 From: inventarSarah Date: Wed, 24 Jun 2026 07:04:41 +0200 Subject: [PATCH 5/6] PR feedback --- docs/platforms/python/tracing/new-spans/index.mdx | 5 +++-- .../python/tracing/new-spans/migration-guide.mdx | 10 ++++++++++ 2 files changed, 13 insertions(+), 2 deletions(-) diff --git a/docs/platforms/python/tracing/new-spans/index.mdx b/docs/platforms/python/tracing/new-spans/index.mdx index 3084d9d02b8f8..781dde2f204ff 100644 --- a/docs/platforms/python/tracing/new-spans/index.mdx +++ b/docs/platforms/python/tracing/new-spans/index.mdx @@ -13,7 +13,7 @@ Stream mode changes this by sending spans to Sentry in batches as they finish. S - **No 1,000-span limit.** In transaction mode, transactions are capped at 1,000 spans. Stream mode has no upper limit since spans are sent in batches. This is especially beneficial for complex generative AI pipelines that easily exceed standard span limits. - **Lower memory usage.** Spans are flushed periodically and don't need to be held in memory until the root span ends. This is especially useful for long-running processes like queue consumers or cron jobs. - **Faster visibility.** Span data arrives in Sentry as your application runs, instead of only after the entire operation completes. -- **No data loss from crashes.** If your process terminates unexpectedly, spans that were already flushed are preserved. In transaction mode, a crash before the root span ends means all span data is lost. +- **Spans are emitted in more failure scenarios.** If your process terminates unexpectedly, spans that were already flushed are preserved. In transaction mode, a crash before the transaction ends means all span data is lost. @@ -142,7 +142,8 @@ with sentry_sdk.traces.start_span(name="parent-operation"): -To start a service span (the equivalent of a transaction), set `parent_span=None`: +A span is automatically promoted to a service span (the equivalent of a transaction) if no other parent is currently active. +If you want to force a new service span, regardless of whether it has a parent span, set `parent_span=None`: diff --git a/docs/platforms/python/tracing/new-spans/migration-guide.mdx b/docs/platforms/python/tracing/new-spans/migration-guide.mdx index d3e6a3c523b30..3b6196fbd3bb5 100644 --- a/docs/platforms/python/tracing/new-spans/migration-guide.mdx +++ b/docs/platforms/python/tracing/new-spans/migration-guide.mdx @@ -104,6 +104,8 @@ Unlike the old methods, `set_attribute` only accepts primitive types (`str`, `in Tags set on the scope with `sentry_sdk.set_tag()` aren't applied to spans in stream mode. Use `sentry_sdk.set_attribute()` to apply data to spans: ```python +import sentry_sdk + sentry_sdk.set_tag("region", "Europe") # applied to errors and other tag-supporting telemetry sentry_sdk.set_attribute("region", "Europe") # applied to spans, logs, metrics ``` @@ -113,6 +115,8 @@ sentry_sdk.set_attribute("region", "Europe") # applied to spans, logs, metrics A few ways of referencing the current span or transaction change in stream mode: ```python diff +import sentry_sdk + # Getting the current span - span = sentry_sdk.get_current_span() + span = sentry_sdk.traces.get_current_span() @@ -139,6 +143,8 @@ If your code reads specific fields off the trace context, access them as direct `sentry_sdk.traces.continue_trace()` replaces the legacy `continue_trace()`. It's no longer a context manager — it sets the propagation context, and the next span you start picks it up automatically: ```python diff +import sentry_sdk + headers = { "sentry-trace": "...", "baggage": "...", @@ -172,6 +178,8 @@ If you use `traces_sample_rate`, no changes are needed. If you use a custom `traces_sampler`, the sampling context has a different structure in stream mode. Span details are available under `sampling_context["span_context"]`, which includes `name`, `trace_id`, `parent_span_id`, `parent_sampled`, and `attributes`: ```python +import sentry_sdk + def traces_sampler(sampling_context): if sampling_context["span_context"]["name"] in IGNORED_SPAN_NAMES: return 0.0 @@ -186,6 +194,8 @@ sentry_sdk.init( `custom_sampling_context` is no longer an argument to `start_span`. Set it on the scope instead, after `continue_trace` (which resets the propagation context) and before `start_span` (which is when sampling happens): ```python diff +import sentry_sdk + - with sentry_sdk.start_span( - name="handle request", - custom_sampling_context={"asgi_scope": asgi_scope}, From 4f477abc530cc26dc37ba6ca99297706944489ba Mon Sep 17 00:00:00 2001 From: inventarSarah Date: Wed, 24 Jun 2026 07:09:51 +0200 Subject: [PATCH 6/6] quick rewrite --- docs/platforms/python/tracing/new-spans/index.mdx | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/docs/platforms/python/tracing/new-spans/index.mdx b/docs/platforms/python/tracing/new-spans/index.mdx index 781dde2f204ff..a4d66e3705034 100644 --- a/docs/platforms/python/tracing/new-spans/index.mdx +++ b/docs/platforms/python/tracing/new-spans/index.mdx @@ -13,7 +13,7 @@ Stream mode changes this by sending spans to Sentry in batches as they finish. S - **No 1,000-span limit.** In transaction mode, transactions are capped at 1,000 spans. Stream mode has no upper limit since spans are sent in batches. This is especially beneficial for complex generative AI pipelines that easily exceed standard span limits. - **Lower memory usage.** Spans are flushed periodically and don't need to be held in memory until the root span ends. This is especially useful for long-running processes like queue consumers or cron jobs. - **Faster visibility.** Span data arrives in Sentry as your application runs, instead of only after the entire operation completes. -- **Spans are emitted in more failure scenarios.** If your process terminates unexpectedly, spans that were already flushed are preserved. In transaction mode, a crash before the transaction ends means all span data is lost. +- **Fewer spans lost to crashes.** If your process terminates unexpectedly, spans that were already flushed are emitted normally. In transaction mode, a crash before the transaction ends means all span data is lost. Stream mode emits spans incrementally as they finish, so more of them survive a crash.