Create iceberg table takes too long

[DimensionWieldr]

Describe the bug
It takes very long to create an iceberg table.

To Reproduce
Steps to reproduce the behavior:

1. Create an iceberg table

CREATE TABLE ice.`default.metadata_testing`
(
    `event_month` Int32
)
ENGINE = Iceberg('s3://protvjoe-1lfyj7kp-iceberg/default/metadata_testing')
PARTITION BY event_month

Query id: 89cf073c-d471-419d-b106-5ad581ff8ad0

Ok.

0 rows in set. Elapsed: 33.453 sec.

Expected behavior
Create table shouldn't take 30+ seconds.

Key information
Provide relevant runtime details.

• 26.3.10.20001 Antalya
• Iceberg table is on ice rest catalog on ACM dev
• In the example, ice is a database created with ENGINE = DataLakeCatalog

[subkanthi]

A namespace already exists error is not handled and CH server seems to keep retrying in loop.

2026-06-16 22:03:45 [00605369-36] INFO c.a.i.r.c.i.r.RESTCatalogServlet > @token POST v1/namespaces
2026-06-16 22:03:45 [00605369-36] WARN c.a.i.r.c.i.r.RESTCatalogServlet > @token POST v1/namespaces: Namespace already exists: my_schema
2026-06-16 22:03:45 [00605369-34] INFO c.a.i.r.c.i.r.RESTCatalogServlet > @token POST v1/namespaces
2026-06-16 22:03:45 [00605369-34] WARN c.a.i.r.c.i.r.RESTCatalogServlet > @token POST v1/namespaces: Namespace already exists: my_schema
2026-06-16 22:03:45 [00605369-36] INFO c.a.i.r.c.i.r.RESTCatalogServlet > @token POST v1/namespaces
2026-06-16 22:03:45 [00605369-36] WARN c.a.i.r.c.i.r.RESTCatalogServlet > @token POST v1/namespaces: Namespace already exists: my_schema
2026-06-16 22:03:46 [00605369-34] INFO c.a.i.r.c.i.r.RESTCatalogServlet > @token POST v1/namespaces
2026-06-16 22:03:46 [00605369-34] WARN c.a.i.r.c.i.r.RESTCatalogServlet > @token POST v1/namespaces: Namespace already exists: my_schema
2026-06-16 22:03:46 [00605369-36] INFO c.a.i.r.c.i.r.RESTCatalogServlet > @token POST v1/namespaces
2026-06-16 22:03:46 [00605369-36] WARN c.a.i.r.c.i.r.RESTCatalogServlet > @token POST v1/namespaces: Namespace already exists: my_schema
2026-06-16 22:03:48 [00605369-34] INFO c.a.i.r.c.i.r.RESTCatalogServlet > @token POST v1/namespaces
2026-06-16 22:03:48 [00605369-34] WARN c.a.i.r.c.i.r.RESTCatalogServlet > @token POST v1/namespaces: Namespace already exists: my_schema
2026-06-16 22:03:51 [00605369-36] INFO c.a.i.r.c.i.r.RESTCatalogServlet > @token POST v1/namespaces
2026-06-16 22:03:51 [00605369-36] WARN c.a.i.r.c.i.r.RESTCatalogServlet > @token POST v1/namespaces: Namespace already exists: my_schema
2026-06-16 22:03:58 [00605369-34] INFO c.a.i.r.c.i.r.RESTCatalogServlet > @token POST v1/namespaces
2026-06-16 22:03:58 [00605369-34] WARN c.a.i.r.c.i.r.RESTCatalogServlet > @token POST v1/namespaces: Namespace already exists: my_schema

[subkanthi]

createNamespaceIfNotExists function does not handle 409 HTTP error.
http_max_tries is the number of times it retries.

void RestCatalog::createNamespaceIfNotExists(const String & namespace_name, const String & location) const
{
    const std::string endpoint = base_url / config.prefix / "namespaces";

    Poco::JSON::Object::Ptr request_body = new Poco::JSON::Object;
    {
        Poco::JSON::Array::Ptr namespaces = new Poco::JSON::Array;
        namespaces->add(namespace_name);
        request_body->set("namespace", namespaces);
    }
    {
        Poco::JSON::Object::Ptr properties = new Poco::JSON::Object;
        properties->set("location", location);
        request_body->set("properties", properties);
    }

    try
    {
        ProfileEvents::increment(ProfileEvents::DataLakeRestCatalogCreateNamespace);
        auto timer = DB::CurrentThread::getProfileEvents().timer(ProfileEvents::DataLakeRestCatalogCreateNamespaceMicroseconds);
        sendRequest(endpoint, request_body);
    }
    catch (...)
    {
        DB::tryLogCurrentException(log);
    }
}