wrong permission on shm kills JAVA_JIT

We found a lot of trace files from several DBs on one of our DB Servers.
They look like:


*********_ora_26444.trc or *********_m000_5598.trc
*** 2017-09-08 15:11:29.181
*** SESSION ID:(632.5995) 2017-09-08 15:11:29.181
*** CLIENT ID:(SYSADMIN) 2017-09-08 15:11:29.181
*** SERVICE NAME:(****_****) 2017-09-08 15:11:29.181
*** MODULE NAME:(*::***:******.****.***.****.******) 2017-09-08 15:11:29.181
*** ACTION NAME:(/) 2017-09-08 15:11:29.181

peshmmap_Create_Memory_Map:
Map_Length = 4096
Map_Protection = 7
Flags = 1
File_Offset = (more...)

SecureFile LOB – managing free blocks

This blog post continues with all the objects and settings from SecureFile LOB - the empty tableSecureFile LOB - the 1st insert SecureFile LOB - the 1st update and SecureFile LOB - more inserts.

It starts with some inserts:
insert into berx.TEST_BLOBS
select 4, comments, file_content
from berx.source_blobs
where id=4;

commit;

insert into berx.TEST_BLOBS
select 5, comments, file_content
from berx.source_blobs
where id=1;

insert into berx.TEST_BLOBS
select 6, comments, file_content
from berx. (more...)

SecureFile LOB – more inserts

This blog post continues with all the objects and settings from SecureFile LOB - the empty tableSecureFile LOB - the 1st insert and SecureFile LOB - the 1st update

The next insert is a small LOB with 2 bytes again:
insert into berx.TEST_BLOBS
select 2, comments, file_content
from berx.source_blobs
where id=2;
--2 byte
The table row points to a new block in the LOB segment:
ROWID   = AABu7gAAEAAA+N/AAA
ROWNUM = 1
LOBID = 00000001000099BF67D1
(more...)

SecureFile LOB – the 1st update

This blog post continues with all the objects and settings from SecureFile LOB - the empty table and SecureFile LOB - the 1st insert



the statement is quite easy:
update berx.TEST_BLOBS
set (comments, file_content) =
(select comments, file_content
from berx.source_blobs
where id=4)
;

The new CLOB is about 11.1 kb in size - so it will require more than 1 block.

Fortunately the number of extents did not change.

New information needs to be gathered (more...)

SecureFile LOB – move online in 12.2

Today we had a "new features in 12.2" workshop. Thank you Mathias Zarick for this great event.
One of the new features was Online Table Move. But the doc was quite unspecific if this also includes LOBs:
Nonpartitioned tables can be moved as an online operation without blocking any concurrent DML operations. A table move operation now also supports automatic index maintenance as part of the move.
Data maintenance on nonpartitioned tables does not (more...)

SecureFile LOB – the 1st insert

This blog post continues with all the objects and settings from SecureFile LOB - the empty table.

The insert of one row with a small (1byte) LOB increases the complexity.
berx.source_blobs contains some BLOBs of different size.
insert into berx.TEST_BLOBS
select 1, comments, file_content
from berx.source_blobs
where id=1; --1 byte

commit;

we have a new extent now


col owner for A10  
col segment_name for A30
select owner, segment_name, file_id, block_id, blocks
from (more...)

SecureFile LOB – spfile parameters

Here is a list of all the spfile parameters I found (and guess are) related to SecureFile LOBs.

This Post will be updated with additional information whenever I collect them.



Parameter

Default value

Description

_dbfs_modify_implicit_fetch

TRUE 12.1.0.2

DBFS Link allows implicit fetch on modify - only on SecureFiles

_enable_securefile_flashback_opt

FALSE 12.1.0.2

Enable securefile flashback optimization

_kdli_STOP_bsz

0 12.1.0.2

undocumented parameter for internal use only

_kdli_STOP_dba

0 12. (more...)