X-CGP-ClamAV-Result: CLEAN X-VirusScanner: Niversoft's CGPClamav Helper v1.22.2a (ClamAV engine v0.102.2) X-Junk-Score: 0 [] X-KAS-Score: 0 [] From: "OCsite" Received: from smtp-beta-2.zoner.com ([217.198.120.71] verified) by post.selbstdenker.com (CommuniGate Pro SMTP 6.3.3) with ESMTPS id 26036596 for webobjects-dev@wocommunity.org; Thu, 17 Jun 2021 14:43:40 +0200 Received-SPF: none receiver=post.selbstdenker.com; client-ip=217.198.120.71; envelope-from=ocs@ocs.cz Received: from smtp.zoner.com (smtp.zoner.com [217.198.120.6]) (using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp-beta-2.zoner.com (Postfix) with ESMTPS id 5F09F18092A0 for ; Thu, 17 Jun 2021 14:43:19 +0200 (CEST) Received: from macbook-pro.ocsluj (unknown [77.240.103.197]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) (Authenticated sender: ocs@ocs.cz) by smtp.zoner.com (Postfix) with ESMTPSA id 1628530000C1 for ; Thu, 17 Jun 2021 14:43:18 +0200 (CEST) Content-Type: multipart/alternative; boundary="Apple-Mail=_405B7D98-5C6F-4F65-A2B3-2E798CAB83EA" Mime-Version: 1.0 (Mac OS X Mail 13.4 \(3608.120.23.2.6\)) Subject: Re: ... too many snapshots? Date: Thu, 17 Jun 2021 14:43:18 +0200 References: To: WebObjects & WOnder Development In-Reply-To: Message-Id: <8C6D4C00-A296-4074-9908-05FC1F1A9A4B@ocs.cz> X-Mailer: Apple Mail (2.3608.120.23.2.6) --Apple-Mail=_405B7D98-5C6F-4F65-A2B3-2E798CAB83EA Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=utf-8 Ramsey, > On 17 Jun 2021, at 0:41, Ramsey Gurley = wrote: > = https://wiki.wocommunity.org/display/documentation/EOF-Using+EOF-Caching+a= nd+Freshness = > In particular, check out Mark Ritchie's Freshness Explorer application = which lets you see how the different layers of the stack propagate = changes. Thanks, but it does not really help. Especially as of >> I admit I am sort of lost in the things. >>=20 >> So far I lived in impression that (if we ignore undo) there's only = one kind of snapshots: OSC-level shared snapshots of = what-was-just-saved-into-DB. >>=20 >> I've tried to research the thing a bit and there seem to be at the = very least the following snapshots: >>=20 >> (i) EC.committedSnapshotForObject >> (ii) EC.currentEventSnapshotForObject >> (iii) EODatabaseContext.snapshotForGlobalID >> (iv) EODatabaseContext.localSnapshotForGlobalID >>=20 >> I regret to say the standard documentation does not help much. I did = some testing and it looks like >>=20 >> - (iii) is the one snapshot I knew: whenever save finishes, it always = contains the newly saved values >> - (i) and (ii) =E2=80=94 which for me always contain same data, = that's weird! =E2=80=94 seem to contain an EC-level snapshot stored at = its (first) willChange. Also it looks like those =E2=80=9Clocally = uncommitted changes=E2=80=9D are based on (one of) these. So far though = I haven't found a case when (i) would differ from (ii)... although, = based on the name, I would actually presume (i) should be the same as = (iii). It very definitely is not. >> - (iv) I don't understand at all :( >>=20 >> Are those things somewhere documented in detail? it never touches those suspicious EC.xxxSnapshotForObject things; and = the particular code it uses, namely, =3D=3D=3D EODatabaseContext databaseContext =3D (EODatabaseContext) = osc.objectStoreForGlobalID(gid); EODatabase database =3D databaseContext.database(); snapshot =3D database.snapshotForGlobalID(gid); =3D=3D=3D just brings a suspicion whether this things differs from (iii)/(iv) = above, and if so, how :( If anybody knows of a good documentation of all those snapshots, how = they differ, when they are created and how they are used, I'd be really = grateful. Thanks and all the best, OC --Apple-Mail=_405B7D98-5C6F-4F65-A2B3-2E798CAB83EA Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset=utf-8 Ramsey,

On 17 Jun 2021, at 0:41, Ramsey = Gurley <webobjects-dev@wocommunity.org> wrote:
https://wiki.wocommunity.org/display/documentation/EOF-Using+EO= F-Caching+and+Freshness
In particular, check out Mark Ritchie's Freshness = Explorer application which lets you see how the different layers of the = stack propagate changes.

Thanks, but it does not really help. Especially = as of

I = admit I am sort of lost in the things.

So far I lived in impression that (if we ignore = undo) there's only one kind of snapshots: OSC-level shared snapshots of = what-was-just-saved-into-DB.

I've tried to research the thing a bit and there = seem to be at the very least the following snapshots:

(i) EC.committedSnapshotForObject
(ii) = EC.currentEventSnapshotForObject
(iii) EODatabaseContext.snapshotForGlobalID
=
(iv) EODatabaseContext.localSnapshotForGlobalID

I = regret to say the standard documentation does not help much. I did some = testing and it looks like

- (iii) is the one snapshot I knew: whenever save = finishes, it always contains the newly saved values
- (i) and (ii) =E2=80=94 which for me = always contain same data, that's weird! =E2=80=94 seem to contain an = EC-level snapshot stored at its (first) willChange. Also it looks like = those =E2=80=9Clocally uncommitted changes=E2=80=9D are based on (one = of) these. So far though I haven't found a case when (i) would differ = from (ii)... although, based on the name, I would actually presume (i) = should be the same as (iii). It very definitely is not.
- (iv) I don't = understand at all :(

Are those things somewhere documented in = detail?

it never touches those = suspicious EC.xxxSnapshotForObject things; and the particular code it = uses, namely,

=3D=3D=3D
EODatabaseContext databaseContext =3D (EODatabaseContext) = osc.objectStoreForGlobalID(gid);
EODatabase database =3D = databaseContext.database();
snapshot =3D = database.snapshotForGlobalID(gid);
=3D=3D=3D

just brings a suspicion whether this things differs from = (iii)/(iv) above, and if so, how :(

If anybody knows of a good = documentation of all those snapshots, how they differ, when they are = created and how they are used, I'd be really grateful.

Thanks and all the = best,
OC

= --Apple-Mail=_405B7D98-5C6F-4F65-A2B3-2E798CAB83EA--