Re: Is there any way to request unique lwlock inside a background worker in PG9.4?
Thanks a lot. On Wed, Oct 17, 2018 at 11:21 PM Andres Freund wrote: > Hi, > > On 2018-10-17 23:11:26 +0800, Hubert Zhang wrote: > > The section "Share Memory and LWLocks" describe the AddinShmemInitLock > which > > is used to protect the ShmemInitStruct() when backend workers initialize > > their shm. My requirement is to how to protect the shm access within the > > bgworkers(not at init stage). This lock should be bgworkers specific. > > Rereead the page please. After you RequestAddinLWLocks() during > initialization, you can use LWLockAssign() to get an lwlock. Which you > then can use as is your pleasure. > > Greetings, > > Andres Freund > -- Thanks Hubert Zhang
Re: Is there any way to request unique lwlock inside a background worker in PG9.4?
Hi Amit The section "Share Memory and LWLocks" describe the AddinShmemInitLock which is used to protect the ShmemInitStruct() when backend workers initialize their shm. My requirement is to how to protect the shm access within the bgworkers(not at init stage). This lock should be bgworkers specific. On Wed, Oct 17, 2018 at 7:51 PM Amit Kapila wrote: > On Wed, Oct 17, 2018 at 3:49 PM Hubert Zhang wrote: > > > > Hi all, > > > > I want to init SHM in a background worker, which is supported in PG9.4. > Also I need to use lwlock to protect the share memory inside the worker > code. > > > > RequestNamedLWLockTranche is the way to handle it, but it's not > supported in PG 9.4, is there any way I could request an unique lock inside > worker init code in PG 9.4? > > > > You might want to look at section "Shared Memory and LWLocks" in the docs > [1]. > > [1] - https://www.postgresql.org/docs/9.4/static/xfunc-c.html > > -- > With Regards, > Amit Kapila. > EnterpriseDB: http://www.enterprisedb.com > -- Thanks Hubert Zhang
Re: Is there any way to request unique lwlock inside a background worker in PG9.4?
On Wed, Oct 17, 2018 at 3:49 PM Hubert Zhang wrote: > > Hi all, > > I want to init SHM in a background worker, which is supported in PG9.4. Also > I need to use lwlock to protect the share memory inside the worker code. > > RequestNamedLWLockTranche is the way to handle it, but it's not supported in > PG 9.4, is there any way I could request an unique lock inside worker init > code in PG 9.4? > You might want to look at section "Shared Memory and LWLocks" in the docs [1]. [1] - https://www.postgresql.org/docs/9.4/static/xfunc-c.html -- With Regards, Amit Kapila. EnterpriseDB: http://www.enterprisedb.com
Is there any way to request unique lwlock inside a background worker in PG9.4?
Hi all, I want to init SHM in a background worker, which is supported in PG9.4. Also I need to use lwlock to protect the share memory inside the worker code. RequestNamedLWLockTranche is the way to handle it, but it's not supported in PG 9.4, is there any way I could request an unique lock inside worker init code in PG 9.4? -- Thanks Hubert Zhang
